I know the list of webcomics I read over there on the left is pretty long, so I'll help you out.
Jesse's Top 5 Favorite Webcomics!
1. Sinfest - Although it tackles much more adult themes, I consider Sinfest to be the closest comic to Calvin & Hobbes that I've read. They both comment on the world in a kind cartoon sort of way and are hopelessly endearing. Above all they just make you feel good.
2. Octopus Pie - Unlike a lot of webcomics Octopus Pie is a story. Even though all the comics work together to tell a story, each individual comic is entertaining in its own right. It is all about the characters and the characters are all captivating and well developed. It is also one of the few comics I can fully recommend starting from the beginning, because it is all fantastic.
3. A Softer World - I tell everyone about this one, but not many actually start reading it. It tends to wander from heart warming to depressing and all the humor in between. I don't know how it does it, but it manages to say things in a way you'd never have thought of.
4. Johnny Wander - For a comic so simple it is wonderful. Not only that, but it creates great mental images that make it surprisingly memorable.
5. The Abominable Charles Christopher - The art in this comic is just breathtaking. Never before have I seen a comic that combines writing and art so perfectly. You can just hear how each line is delivered. It goes between a main story involving a simpleton Yeti and the side stories of the various creatures of the forest. If I liked the main story more this comic would probably be #1, but it is a little too...poetic at times. Regardless it is a ton of fun.