They're all pretty good, but there were assuredly my favorites:
Rock Band: The White Stripes will deduct points if you hit more than one of the drum pads at any given time.
Rock Band: Prince will force you to play all of the instruments at the same time.
You will have to reprogram the colored buttons in order to play Rock Band: Sonic Youth.
Every time you play Rock Band: U2 absolutely perfectly, an indebted country becomes debt-free.
Rock Band: The Rolling Stones will require that you play the same 20 songs for 30 years.
Rock Band: Creedence Clearwater Revival will sue you if you actually play any of its songs.
Rock Band: Neil Young has been delayed until 2029.
Rock Band: Ryan Adams will never quite live up to its potential.