I just love Tetsuya Mizuguchi's REZ from the day I got it in 2002 for my Sega Dreamcast, and still playing it in the guise of the new Xbox360 HD version that came out recently in 2008.
Aesthetically to me, a continuation from Tron. For me, Rez appeared whilst I was still doing VJing and Motion Graphics, so felt right at place when I got to play it. What was memorable though - and I can't remember something being similar at the time - was the fusion of the music and the game elements. Though basically a Game on Rails shooter, the exchange of the usual explosion and gun sounds for musical notes and percussive sounds, produced for me, a really involved music video.
example of gameplay
Both Rez and Tron, are definite visual influences on my Second life creations (particularly now they've added glow effect) - especially with my last sound toy I made called Pusher-Tron