My first post was planet colors from F-Zero GX. I posted it beause I think it suited the high speed racing perfectly and thought that it was the type of music/game that many people would not have thought to make a post about.
... Then I ate some beef and went crazy, posting a load of Nintendo game music. Mario Bros 3 mini boss/underground(?) - just always thought it was awesome. Windwaker mini boss - I couldn't decide between that and the standard enemy music but of course the mini boss is more action themed. Pokemon Fire Red Legendary Battle - I've always loved Pokemon battle music(as mcuh I hate to say it). I also love remixes, so noticing the slight changes in the legendary battle music was rather fun for me.
Hmm then was it the boss theme from Mario Bros 2?(Doki Doki Panic -_-; Dunno, just kinda liked it.