Look at this fantastic tutorial provided by abduzeedo. It shows how to create an amazing and realistic water text using:
Adobe Illustrator – to write the text
Cinema 4D – to move in a 3D enviroment that will give a nice effect
Photoshop – to place some real water photos and give a very realistic feeling to the image
Of course you can use other 3D apps (for example 3D Studio MAX – not available for mac).
The result is great and can be applied for different purposes!