Interactive Fiction

• The Interactive Fiction Archive, the Great Library of IF. Most of what is worth knowing about IF is here, somewhere. On the other hand, unless you're looking for something in particular, you'll be better served by...
• Baf's Guide to the Interactive Fiction Archive, which catalogs the games at the archive by genre, development system, quality, and a host of other details. Reviews are available for some games.
• XYZZYnews and the Society for the Promotion of Adventure Games are two organizations which publish news for the IF Community, including reviews, interviews with authors, and development and design articles.
• The Annual Interactive Fiction Competition is probably the biggest event of the year for the interactive fiction community, and produces a wide variety of games. Some of the best games of the modern era of IF are actually IF-Comp entries.
• The Interactive Fiction Wiki triues very hard to collect in one place all knowledge about interactive fiction in the known universe. Like most wikis, it's chock-full of information of varying levels of accuracy.

Comics

• Phil and Kaja Foglio's Girl Genius used to be a print comic, but now it's all webified (and made the transition successfully!). Read and enjoy, and if you like the arto and/or business model, buy some books!
• John Allison's Scary-Go-Round is pretty delightful.
• Jeffrey Rowland's Wigu is cute but dormant. The only Jeffrey Rowland orject I know of that's updating is his less charming but nonetheless funny Overcompensating.
• Jeph Jacques' Questionable Content has some dull lulls, but when it actually has plot, it's an enjoyable read.
• Chances are, you're either already a fan of Randy Munroe's xkcd or you're not interested. But if you've never heard of it, check it out.
• Josh Fruhlinger's Comics Curmudgeon is a one-stop shop for all your newspaper-comic snark. As an added side-effect, you'll acquire newfound appreciation for all those interminable soap-operatic comics you never actually read as a kid.

Other Cool Stuff

• BrettSpielWelt is an impressively detailed online board-gaming site with all of the favorites of the twinkie crowd. It's mostly German-speaking and not everything attached to it is translated, but, mmm, free online gaming.
• The ifMUD is mostly a glorified chat-room, and it's not just for IF any more (if indeed it ever was).
• Darkstar is the UCSD science fiction and board-gaming society. I'm no longer in San Diego, but they're still a great bunch.