Indie comix creator Tara Tallan's site Girlamataic Webcomics publishes an RSS feed of half-a-dozen free indie comic serials created by women, including her own long-running serial Galaxion. Tara and I worked together at Bakka, Toronto's science fiction bookstore, and she turned me on to many wonderful funnybooks, most notably Warren Ellis's Transmetropolitan.
Update: Stacie sez, "Certainly Tara makes great comics, but she doesn't own Girlamatic. Girlamatic has been around for a few years now, and is currently edited by Lisa Jonte, and was previously edited by Lea Hernandez." — my mistake! I found out about it through Tara and assumed she'd started it…