gmer412 said:
Here are some really good recent ones. The one at the bottom still cracks me up. To the naysayers: how are these not funny?
http://xkcd.com/540/
http://xkcd.com/530/
http://xkcd.com/528/
http://xkcd.com/518/
The "Base System" comic is very good. It gets points because it's an elaborate diagram illustrating what's supposed to be a simple metaphor, and even more points because it actually communicates something interesting.
The "Flow Charts" comic is pretty good, too, though it communicates far less.
The "Windows 7" comic isn't very good. It just restates an annoyingly overdone geek trope. Blah, blah, Vista sucks, we get it. I find it mildly amusing, but it's no better than the random bullshit I use to fill dead space in a conversation. If you ran into a webcomic where all of the strips were like this one, it wouldn't be worth reading (if it was also poorly-drawn, ancient, and stuck up its own ass, that webcomic would be called "User Friendly").
The "I'm An Idiot" comic is cute but not funny, in the way that most XKCD is (and tries to be) cute but not actually very funny.
What these illustrate is that, overall, Randall Munroe does one very good strip every week or two. The rest are just filler. That makes his comic significantly better than most. I don't think it deserves the geek worship it receives -- particularly because of the way it plays up the easy geek jokes too often.
-- Alex