http://www.spxpo.com/
Small Press Expo September 26-27th Bethesda, MD.
One day pass $10 Two day pass $15.
This convention was awesome last year, by far my favorite. They have excellent panels and activities, a lot of fellow artists are roaming around (more than your typical convention), and the guest list is awesome. Namely there are a lot of Web Comic icons in attendance including:
John Allison (Scary Go Round)
Kate Beaton (Hark! A Vadrant)
Aaron Diaz (Dresden Codak)
Ryan North (Dinosaur Comics)
and I believe KC Green (Gun Show) is going.
I'm farther away now, but I'm still going to attempt to be there.