Mike Wieringo, comic book artist, recently passed away at the age of 44 from heart failure. He wasn't my favorite artist, possibly because his art seemed a bit more cartoony than I like, but I did read his blog on occassion and I read a few of the titles he worked on, most notably his epic run on The Flash with Mark Waid in the mid-90s. Some people are sharing their favorite 'Ringo covers in this thread.
Roy Edroso, former punk and underground musician, is probably my favorite political writer (I say probably because I haven't given it much thought). He is very good at cutting through the bullshit, and his best work is when he picks apart those who view art strictly as propaganda and nothing else. However, that's only the tip of his penis, for he does well on so many other topics. Take his examination of people who are desperate to be free of diversity ("Race Men"), or the confusing minds of pro-war conservatives ("Hawks & Sheeple"), or even the me-first, you-never attitude of libertarians ("The Trouble With Libertarians, Part 45,882"). As an added bonus, his comments section is among the best on the Internet, a healthy mix of quality and quantity. I imagine his articles and blog are only enjoyable if you are left-leaning, but even in terms of technical proficiency, he is a hell of a writer.
Finally, this comic is so true to reality it's almost sad. It doesn't even touch on HMOs, which means that if you manage to corral health insurance from an employer, you still probably can't see the doctor you want and you need referrals everytime you want to have something checked. And don't even think about preventitive medicine, not even in passing.