SteSoft Realtime Direct3D Water
This is a realtime water surface simulation program I wrote recently. It uses a grid-mesh that I generate on the fly and models the water with each point in the grid using a simple spring algorithm (position / velocity vector / potential energy). To run this, you need Win98/Win98SE and DirectX 6.1 I doubt it will run very fast if you dont have a very fast 3-D Card (TNT2 ULTRA recommended).
Download it HERE
Water with an opaque surface
Water with alpha-transparent surface (note stesoft logo on bottom of
Water with wireframe surface (This is just to show the grid that makes
up the surface)