OSDev.org

Since there are many rethro fans here. Check out
remix.kwed.org/

There you kan find kickass remixes on your old favorite C64 game tunes. A lot of synth and techno of course.
Be sure to try the Out Run Pazzing breeze theme aswell as Last Ninja remixes!!

I'm almost blowing away my speakers!!!

I still play SID files with SidPlay

fmod for mod/s3m/it/xm playing

and winamp ofcourse for mp3

heh. LastNinja SIDS are pretty good.
Vibrants made some cool c64 sids

One of my favorite video game remix sites is http://remix.overclocked.org

When I found the site I went nuts and downloaded every single song (at the time it was a little over a gig). Great site though, lots of remixed C64 and Nintendo tunes.