As part of their ongoing "Comics issue" Nerve.com have posted a list of "The 20 Comics that can change your life".
Some obvious ones, but some interesting choices like there always are in lists like this.
Alias by Bendis
Preacher by Ennis & Dillon
Optic Nerve by Adrian Tomine
Hate by Peter Bagge
Transmetropolitan by Ellis & Robertson
Diary of a Teenage Girl by Phoebe Gloeckner
Persepolis by Marjane Satrapi
Blue Monday by Chynna Clugston
Fun Home: A Family Tragicomic by Alison Bechdel
Like a Velvet Glove Cast in Iron by Daniel Clowes
Fortune and Glory by Brian Michael Bendis
Kabuki by David Mack
Love and Rockets by Los Bros Hernandez
Heavy Liquid by Paul Pope
Sandman by Neil Gaiman
Miracleman by Gaiman, Moore et al.
Zippy the Pinhead by Bill Griffith
Usagi Yojimbo by Stan Sakai
Fantastic Four Issues #1-#102 by Stan Lee and Jack Kirby
Planetary by Warren Ellis