One large mask brush ofr yah. 700px by 500px
The smaller image in the corner is a better representation of what it will look like as brush. The fun colors can be misleading, I guess.
For Photoshop CS and up... image pack included.
photoshop 7 ^ brushes that can be defined for any image aplication (gimp, Photoshop, Painter, paintshop pro). As the only policy, please leave a comment if using and do not redistribute any files from my account without permission.