using UnityEngine;
using System.Collections;
public class NotifyHandler : MonoBehaviour {
public Camera mainCamera;
public Camera guiCamera;
public GameObject prefab;
public void fire( Vector3 clickedPos_ )
{
  GameObject _gameObj = Instantiate( prefab, clickedPos_, Quaternion.identity ) as GameObject;
  // No mean yet, just align as child
  SomeTools.AppendChildAndReset( gameObject, _gameObj );
  // run floating script
  FloatingTextUp2D _floatTxtUp = _gameObj.GetComponent<FloatingTextUp2D>();
  _floatTxtUp.initAndStartMoving( clickedPos_, mainCamera, guiCamera );
}
}

using UnityEngine;
using System.Collections;
public class UIInputReactor : MonoBehaviour {
void Update()
{
  if( Input.GetButtonDown("Fire1") ) {
    // 화면을 임의 클릭해서, 뭐든 있는 위치를 캐치해서,
    Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
    RaycastHit hit;
    if( Physics.Raycast(ray, out hit, 100) ) {
      // NotifyHandler 오브젝트에 메시지 발송 (fire 실행)
      GameObject _obj = GameObject.Find("NotifyHandler");
      _obj.SendMessage( "fire", hit.point );
    }
  }
}
}

FloatingText2D.cs

using UnityEngine;
using System.Collections;
 
public class FloatingText2D : MonoBehaviour
{
  private UILabel   	__label;
	private Vector3			__pos;
	private Transform		__t;
 
 
	public bool 			followTarget = true;
	public Vector3			defaultSize = new Vector3(1,1,1);
 
	public GameObject		targetObject;
	public Camera			worldCamera;
	public Camera			guiCamera;
	public TweenPosition	tweenPos;
 
 
	public void init( string text_, GameObject gameObj_ )
	{
		this.text = text_;
		this.target = gameObj_;
	}
 
	public void init( string text_, Color clr_, GameObject gameObj_ )
	{
		this.color = clr_;
		this.text = text_;
		this.target = gameObj_;
	}
 
	public void spawnAt( GameObject targetObj_, Vector3 size_, Transform parent_ )
	{
		target = targetObj_;
		__t.parent = parent_;
		defaultSize = size_;
	}
 
	public void followingObject()
	{
		__pos = worldCamera.WorldToViewportPoint( targetObject.transform.position );
		__pos = guiCamera.ViewportToWorldPoint( __pos );
 
		__pos.z = 0f;
		transform.position =  __pos;
	}
 
	// Use this for initialization
	void Awake()
	{
		__t = transform;
		__label = GetComponent<UILabel>();
	}
 
	void Start()
	{
		if( guiCamera == null )
			guiCamera = NGUITools.FindCameraForLayer( gameObject.layer );
 
		__label.transform.localScale = new Vector3( __t.transform.localScale.x * defaultSize.x, __t.transform.localScale.y * defaultSize.y, 1f );
	}
 
	void LateUpdate()
	{
		if( followTarget ) followingObject();
	}
 
	// property
	//
	public string text
	{
		get { return __label.text; }
		set { __label.text = value; }
	}
 
	public Color color
	{
		get { return __label.color; }
		set { __label.color = value; }
	}
 
	public Vector3 size
	{
		get { return __label.transform.localScale; }
		set { __label.transform.localScale = value; }
	}
 
	public TweenPosition tweenPosition
	{
		get {
			TweenPosition _tp = GetComponent<TweenPosition>();
			if( _tp == null ) _tp = targetObject.AddComponent<TweenPosition>();
			return _tp;
		}
	}
 
	public GameObject target
	{
		get { return targetObject; }
		set { 
			targetObject = value; 
			worldCamera = NGUITools.FindCameraForLayer( targetObject.layer );
		}
	}
}

FloatingTextUp2D.cs

using UnityEngine;
using System.Collections;
 
public class FloatingTextUp2D : MonoBehaviour {
  private UILabel 		__label;			// from ScriptIncluded
  private Vector3			__pos;
  private Vector3			__initPos;
 
  public Camera			guiCamera = null;
  public Camera			worldCamera = null;
 
  public GameObject		targetObject = null;
  public int				tweenTime = 2;
  public int				tweenDistance = 50;
 
	// class spec function
	//
	public void destroySelf() {
		Destroy( gameObject );
	}
 
	public void initAndStartMoving( Vector3 initPos_, Camera mainCam_ = null, Camera guiCam_ = null )
	{
		if( mainCam_ != null ) worldCamera = mainCam_;
		if( guiCam_ != null ) guiCamera = guiCam_;
		startMoveUp( initPos_, 2, 50 );
	}
 
	public void startMoveUp( Vector3 initPos_, int tweenDuration_, int tweenEnd_ )
	{
		__initPos = initPos_;
		calculatePosition( initPos_ );
 
		TweenPosition _tp = this.tweenPosition;
		_tp.duration = tweenDuration_;
		_tp.from = transform.localPosition;
		_tp.to = _tp.from + Vector3.up * tweenEnd_;
		_tp.eventReceiver = gameObject;
		_tp.callWhenFinished = "destroySelf";		
	}
 
	public void calculatePosition( Vector3 pos_ )
	{
		__pos = worldCamera.WorldToViewportPoint( pos_ );
		__pos = guiCamera.ViewportToWorldPoint( __pos );
		__pos.z = 0f;
		transform.position =  __pos;
	}
 
	// Unity3d reaction function
	//
	public void Awake() {
		__label = GetComponent<UILabel>();
	}
 
	void Start()
	{
		if( guiCamera == null ) guiCamera = NGUITools.FindCameraForLayer( gameObject.layer );
		if( worldCamera == null ) worldCamera = Camera.mainCamera;
		__label.MakePixelPerfect(); // why bigger???
		if( targetObject != null ) {
			startMoveUp( targetObject.transform.position, tweenTime, tweenDistance );
		}
	}
 
	// Property helper
	//
	public TweenPosition tweenPosition {
		get {
			TweenPosition _tp = GetComponent<TweenPosition>();
			if( _tp == null ) _tp = gameObject.AddComponent<TweenPosition>();
			return _tp;
		}
	}
}

FloatingTextUp2D.cs

using UnityEngine;
using System.Collections;
 
[RequireComponent( typeof( TweenPosition ) )]
public class FloatingTextUp2D : MonoBehaviour
{
  public enum Side
	{
		Left,
		Right,
		Center,
		NoOutOfScreen,
		NoTouch
	}
 
	private UILabel 		mLabel;			// from ScriptIncluded
	private Vector3			mObjPos;
 
	public Camera			guiCamera = null;
	public Camera			worldCamera = null;
	public GameObject		targetObject = null;
	public float			tweenDuration = 2.5f;
	public float			tweenDistance = 350f;
	public Side				startSide = Side.NoOutOfScreen;
	/// <summary>
	/// move up by Percent from -1 ~ 1. 0 is middle of scrren. If this is false, tweenDistance used to end of tween moving.
	/// </summary>
	public bool				moveUpByPercent = false;
	/// <summary>
	/// how much move up? this value from -1 to 1. 0 is middle of screen.
	/// </summary>
	[Range(-1, 1)]
	public float			moveUpPercent = 0f;
	/// <summary>
	/// Auto Scale by screen width. if zero, use original size. if 1, full width.
	/// </summary>
	[Range( 0, 1 )]
	public float			scaleByScreen = 0f;
	/// <summary>
	/// If scaleByScreen not setted. use this.
	/// </summary>
	//public Vector2			defaultSize = new Vector2( 1, 1 );
 
	public void destroySelf()
	{
		Destroy( gameObject );
	}
 
	// get UILabel width, height roughly. code from UILabel.MakePixelPerfect()
	public Vector2 getUILabelSize()
	{
		float pixelSize = (mLabel.font.atlas != null) ? mLabel.font.atlas.pixelSize : 1f;
		Vector3 scale = mLabel.cachedTransform.localScale;
		if( scaleByScreen != 0f )
			scale.x = ((guiCamera.pixelWidth / mLabel.relativeSize.x) * scaleByScreen);
		else
			scale.x = mLabel.font.size * pixelSize;
		scale.y = scale.x;
		scale.z = 1f;
 
		return (mLabel.relativeSize * scale.x);
	}
 
	public Vector3 fixPosition( Vector3 value_ )
	{
		Rect rect = new Rect();
		rect = guiCamera.pixelRect;
 
		if( startSide != Side.NoTouch )
		{
			Vector3 _tmpPos = guiCamera.WorldToScreenPoint( value_ );
			Vector2 _labelSize = getUILabelSize();
			float _middleX = Mathf.Abs( _labelSize.x * mLabel.pivotOffset.x );
 
			if( startSide == Side.Center )
			{
				_tmpPos.x = (rect.xMin + rect.xMax) * 0.5f;
			}
			else if( startSide == Side.Left )
			{
				_tmpPos.x = (rect.xMin + _middleX);
			}
			else if( startSide == Side.Right )
			{
				_tmpPos.x = (rect.xMax - _middleX);
			}
			else if( startSide == Side.NoOutOfScreen )
			{
				if( (_tmpPos.x - _middleX) < rect.xMin ) _tmpPos.x = rect.xMin + _middleX;
				if( (_tmpPos.x + _middleX) > rect.xMax ) _tmpPos.x = rect.xMax - _middleX;
			}
 
			value_ = guiCamera.ScreenToWorldPoint( _tmpPos );
		}
		return value_;
	}
 
	public void adjustPosition( Vector3 pos_ )
	{
		mObjPos = worldCamera.WorldToViewportPoint( pos_ );
		mObjPos = guiCamera.ViewportToWorldPoint( mObjPos );
 
		mObjPos = fixPosition( mObjPos );
 
		mObjPos.z = 0f;
		transform.position =  mObjPos;
	}
 
	public void adjustScale()
	{
		if( scaleByScreen == 0f )
		{
			mLabel.MakePixelPerfect(); // why bigger???
			return;
		}
		else if( mLabel.font != null )
		{
			float pixelSize = (mLabel.font.atlas != null) ? mLabel.font.atlas.pixelSize : 1f;
 
			//pixelSize = 4;
 
			Vector3 scale = mLabel.cachedTransform.localScale;
			//scale.x = mLabel.font.size * pixelSize;
			scale.x = ((guiCamera.pixelWidth / mLabel.relativeSize.x) * scaleByScreen);
			scale.y = scale.x;
			scale.z = 1f;
 
			Vector2 actualSize = mLabel.relativeSize * scale.x;
 
			int x = Mathf.RoundToInt( actualSize.x / pixelSize );
			int y = Mathf.RoundToInt( actualSize.y / pixelSize );
 
			Vector3 pos = mLabel.cachedTransform.localPosition;
			pos.x = Mathf.FloorToInt( pos.x / pixelSize );
			pos.y = Mathf.CeilToInt( pos.y / pixelSize );
			pos.z = Mathf.RoundToInt( pos.z );
 
			if( mLabel.cachedTransform.localRotation == Quaternion.identity )
			{
				if( (x % 2 == 1) && (mLabel.pivot == UILabel.Pivot.Top || mLabel.pivot == UILabel.Pivot.Center || mLabel.pivot == UILabel.Pivot.Bottom) ) pos.x += 0.5f;
				if( (y % 2 == 1) && (mLabel.pivot == UILabel.Pivot.Left || mLabel.pivot == UILabel.Pivot.Center || mLabel.pivot == UILabel.Pivot.Right) ) pos.y -= 0.5f;
			}
 
			pos.x *= pixelSize;
			pos.y *= pixelSize;
 
			mLabel.cachedTransform.localPosition = pos;
			mLabel.cachedTransform.localScale = scale;
		}
	}
 
	public void startMoveUp( Vector3 initPos_, float tweenDuration_, float tweenEnd_ )
	{
		adjustScale();
		adjustPosition( initPos_ );
 
		TweenPosition _tp = this.tweenPosition;
		_tp.eventReceiver = gameObject;
		_tp.callWhenFinished = "destroySelf";
		_tp.from = transform.localPosition;
 
		if( moveUpByPercent )
		{
			_tp.to = Vector3.up * (Screen.height * 0.5f) * moveUpPercent;
			_tp.to.x = _tp.from.x;
		}
		else
		{
			_tp.to = _tp.from + Vector3.up * tweenEnd_;
		}
 
		if( tweenDuration_ != 0 )
		{
			_tp.duration = tweenDuration_;
		}
	}
 
	public void initAndStartMoving( Vector3 initPos_, Camera mainCam_ = null, Camera guiCam_ = null )
	{
		if( mainCam_ != null ) worldCamera = mainCam_;
		if( guiCam_ != null ) guiCamera = guiCam_;
 
		startMoveUp( initPos_, tweenDuration, tweenDistance );
	}
 
	// Unity3d reaction function
 
	public void Awake()
	{
		mLabel = GetComponent<UILabel>();
 
	}
 
	void Start()
	{
		if( guiCamera == null ) {
			guiCamera = NGUITools.FindCameraForLayer( gameObject.layer );
		}
		if( worldCamera == null ) {
			worldCamera = Camera.mainCamera;
		}
 
		if( targetObject != null ) {
			startMoveUp( targetObject.transform.position, tweenDuration, tweenDistance );
		}
	}
 
	public TweenPosition tweenPosition
	{
		get {
			TweenPosition _tp = GetComponent<TweenPosition>();
			if( _tp == null ) _tp = gameObject.AddComponent<TweenPosition>();
			return _tp;
		}
	}
}