Here's one approach to that grid rippling effect they had in Geometry Wars. It utilizes vertices and renders an 80x80 grid which you can play around with. I know this isn't an exact replica of the Geometry Wars background effect (which I think is rendered in 3D), but hopefully it should be nice and easy to use, and hopefully it can be edited to provide an interesting background for shooting games.
This example is ripped from my own Geometry Wars inspired game, Grid Defender 2
If you support this project, please check out the topic above and post some feedback
Download link - http://www.nfyre.com/dynamic.html
.GM6 provided by garrlker
Edited by Necromian, 10 January 2009 - 06:52 PM.