All materials on this site are posted under a Creative Commons Attribution No Derivatives 3.0 license. The breakdown:
You can copy stuff. Really. But you can't sell it.
If you copy stuff and use it in a public space (ie your website or dorm lobby or myspace page, even if only your friends will ever see it) you have to include a brief and obvious bit of text attributing the work to me. It can be as simple as 'Awesome art from Liz at Inksplot Studios.' See how easy it is to be an upstanding citizen?
No remixes. But if you contact me and ask if it's okay, I might waive this condition for a good cause or a neat project.