The Collins Compendium of Free Online Comic Books
Lots of additions to the Vertigo and Marvel lists, plus a bunch of new stuff from Image, Virgin, and more. I've barely scraped the surface of what Tokyopop has to offer for free. I removed a lot of dead links too (including, unfortunately, the links to the Elseworlds 80-Page Giant pages). All in all, the list now tops 300 comics you can read for free. Maybe even 400, with all of Tokyopop and Dark Horse's offerings.
If you aren't reading Ed Brubaker's Criminal or Warren Ellis' Fell yet, you can read the first issue of each online. I recently added both to my pull list. The first five issues of 52 are online too, as are the first five issues of Powers. This time of year, you may be interested in the PvP Christmas Special. But my favorite new addition may be a short story that was only printed in the 2001 Small Press Expo Anthology, Max Hamm, Fairy Tale Detective in "Just Right."
I'll be tweaking the page further in the next few days, so if there are issues I'm missing, let me know in the comments section.