Wow….I didnt realize how long it had been since I visited BittBox. I went there looking for some grunge brushes and found whole slew of new things. If you have never checked out BittBox, I highly suggest you do. He regularly puts out some great free resources. From photoshop brushes to high quality vectors, this guy does it all. He even has a handfull of basic tutorials and other cool things.

Go check it out his site, BittBox

Here are some of my favorite resources from there:

Free High Res Photoshop Brushes: Grungy Texture

Free Hi-Res Watercolor Photoshop Brushes

Free Hi-Res Photoshop Brushes: Messy Spraypaint