"Don't You Forget it" by Glenn Lewis reached #30 (Lewis has an album set to come out sometime this year, so maybe he won't be on this list for much longer?)
"What if She's an Angel" by Tommy Shane Steiner reached #39 (He hasn't recorded anything since 2002.)
"Addictive" by Truth Hurts reached #9 (The base track "Addictive sampled was from an Indian composer without credit. He subsequently sued.)
"Days Go By" by Dirty Vegas reached #14 (Much like The Wiseguys, Dirty Vegas' song was featured in a Mitsubishi commercial, catapulting them into popularity. House music mixers should take a leaf out of their books.)
Honorable Mention:
"Youth of the Nation" by POD reached #28