Not just Photoshop

Did you know that the latest version of GIMP supports the use of .abr files? (thats the file extension that photoshop brushes use)

GIMP stands for GNU Image Manipulation Program. It is a free program for tasks like photo retouching, image composition and image authoring. Like photoshop, it uses layers, has filters, custom brushes etc. It’s a great alternative to photoshop, and now you don’t have to go through the hassle of converting brush sets.

It does has a steeper learning curve than photoshop but there are plenty of good beginners tutorials out there if you search.