Version: Photoshop 7+, Photoshop Elements 2+, GIMP 2.2.6+
If you'd prefer these as seamless patterns, check out these: [link]
These are also seamless, if you were to perfectly overlap them... but that's harder to do with brushes. So, if you're planning on a repeating pattern, I'd check out the patterns.
ALSO, these had to be SIZED DOWN slightly to fit within the 30MB limit. These are all 1000 x 1000 pixels. My original version had more than half the brushes at 1500 x 1500 pixels. If you'd rather download that higher res version, you can find them here:
If you're interested in the images that make up the brushes themselves, check here: [link]