A flash-based web site for creating your own comic book from a collection of pre-rendered panel layouts, backgrounds, characters, and objects. Actually pretty impressively flexible.
This tool is really cool. You can create multi-panel web comics with this intuitive little tool. Choose from a palette of characters and objects. Very funny, easy and flexible.
The article on SoYouWanna on making comics. Has a particular focus on breaking into the comics industry, but has a little info on self-publishing, too.