Any name that is jibberish (kdfsjglg... erm... he was around a lot in '07)
Any name that rips off of a video game (mariomusicmaker1, nessbeatsfox)
RedCoin is cool, because he gives a subtle hint; not a direct name
Any pompous name (All-American-Badass)
Any name involving skulls, dragons, fire or death
names that use 'X's to look 'cooler'
useless numbers in the name (AKA; no direct meaning)
Misspelling common words to seem edgy (oh wait--)
What is ok:
Names that can be pronounced
Your actual name
a poetic and/or intellectual name