Webcomics let comic artists take their work to a new level. You can do things on the computer screen in 24-bit color that you can't possibly do in the dithered color on the Sunday comics page. There are some amazing folks out there. I'm always blown away by how the best comic artists can give you a dead-on unambigous mental picture of a place or object with just a few strokes. I thought people might be interested in sharing their favorites and discussing the art.
As far as artwork goes, I have one clear favorite: Penny Arcarde. Although the subject matter (computer gaming, usually) isn't for everyone, the strip itself is something all artists can appreciate. On the example I've linked to, look at how the alarm clock glows and lights up the bed, and look at the reflection in the window on the last panel. Wonderful stuff!
Last I knew, he draws the original in pencil, scans it, then inks and colors in Photoshop.