Rush
Led Zeppelin
RHCP
Pearl Jam
Chris Cornell (Audioslave, Soundgarden, Alice Mudgarden, TOTD)
Tons of runner ups for me in no particular order, some of which may bump into my top 5 from time to time): John Fruisciante (if you haven't heard his solo stuff you are missing out), Alice in Chains, Nirvana, Jane's Addiction, Foo Fighters, Clapton, Queen, Bad Religion, Rancid, The Descendents, Herb Alpert and the Tijuana Brass Band, Beastie Boys, Bob Dylan, NOFX, Phish, The Clash, Radiohead, Sublime, The Who...)
Edit: Not a top 5, but if you like The Clash, and haven't heard of The Crunch, check them out: