here is a list of some of the webcomics that have drained large chunks of time from my life. I usually go a few months to a year then binge on them (just did this for the last few days)

• Sluggy Freelance Huge ass comic that will cause a sage-length beard to sprout last read
• Something Positive Fucked. Up. Comic. Last Read
• PVP not a gamer but geeks are geeks whatever they do last read
• Suburban tribe never worked at an add agency, but still like the randomness last Read
• Wapsi Square whats funnier than a short chick with big breasts that keeps three drunk chicks that are separated elements of an Armageddon beast. As well as the Aztec god of alcohol last read
• Zebra Girl the main character, Jack the Plaid, a perky goth, a anthropomorphic bunny-drunk, a dufus werewolf..... last read
• Questionable Content (Hipster coffee shop snarkyness. love the one liners and randomness that ensues.)
• XKCD (simple line drawing witha bunch of mat and scienc jokes that go WAYYY over my head. stillpretty damn funny. don't forget to mouse over the pictures!
• Freak Angels (beautifully made post-pocalyptic, steampunky comic)
• Girl Genius [htp;//www.girlgeniusonline.com] (Just a damn good comic)
• Men in Hats (simple art, bunch of characters, fucked up scripts)
• Penny Arcade (a classic. Not sure about the jokes when they get really game specific but random violence aways makes a schadenfreudian punchline.)
• Dresden Codak (nice comic with an anime feel. deals with higher rder philosopy that goes mostly over my head; had wikipedia things over a dozen times in a few comics. best one I can think of off-hand is the one where Schroedingers cat offends the Egyptian gods.
• Order of the Stick (if you like roleplaying games, a I do, then you will freaking like this comic. simple-ish stick art and funny rule-mongering with a large dash of creative confusion due to different edition rules makes the inner geek go SQUEEE!
• Last Blood - hardcore comic about vampires protecting the last human survivors of the zombie apocalypse so both species can survive.
• Least I Could Do- fucking funny-ass comic about an amoral narcissist with a generous streak and habit to break the fourth-wall of the comic to grab props and costumes for great comediac effect. lots of one liners.
• Dueling Analogs
• extrlife
• Perry biblefellowship
• ScarygoRound