The SLI statement is false; SLI is NOT a requirement for Nvidia 3D vision. Anything newer than a 9800GT will satisfy nearly all of the requirements for 3D gaming (won't be fast though
However, you'll need a 3D Monitor or TV, as previously mentioned, and that is really the expensive part. The Asus 3D monitor is great
Many of the games rated as "Excellent" work very well, but obviously the 3D-ready games were programed for 3D vision.