I'll just go through what I've got most in my current playlist...
Apollo 440, Audio Bulleys, Bentley Rythm Ace, Chemical Brothers (always a must), Chikinki, Daft Punk, Fat Boy Slim, Felix Da Cathouse, Foo Fighters, Franz Ferdinand, Girl School (hehe), Gorillaz, Hives (woo), Ima Robot, Jamiroquai, Jet, Kasabium, Leftfield, Lester, Moby, Muse, Orbital, Overseer, Prodigy (old and new), RATM, Rush, Soulwax (excellent), Crystal Method, Strokes (good), Vines...
The list of what I'm really into though is endless... However I tend to stay away from heavy metal (Metallica, Slipknot (not sure if that's really heavy metal though), Korn, Guns n Roses...) and some of the reproduced RnB shiz that's been out recently...