As you can see in my other post:
Action Action: Indie rockers, used to be in the hardcore genre I believe, but made a huge turn around. Their new sound is amazing, and I love their music and lyrics. (Paper Cliche is probably their best song on the second cd)
Not too mainstream, but they are pretty well-known. Listen to Paper Cliche.
http://www.purevolume.com/actionaction
The Faint: Amazing New Wave/Indie rock band. Their concerts are among the best I've ever been too. Every band member knows how to play the other member's instruments, so in the middle of the song they would all be switching, it's nuts. Everyone of their CDs is gold and I don't think I've ever heard a bad song from them. All their songs are catchy. Some are serious and some are meant to dance to. I can't say anything more, but listen to them for yourself. The mixes available on their site do them no justice. I recommend listening to H-O-S-P-I-T-A-L, Symptom Finger, Agenda Suicide, Worked Up So Sexual, Total Job, Glass Danse, Posed to Death, Drop Kick the Punks, Paranoiattack ... They have 5 cd's out, I suggest you go get yourself a copy of one. =]
http://www.thefaint.com