A free and open source viewer that lets you preview your abr files.
Here’s what the author says about the ABRviewer:
“There are lots of wonderful brush sets for Photoshop in the web… too many to install them all just to see what they look like! now you can have the preview of a set without having to install it… without having to run Photoshop! You can even adjust thumbnails size and you can have the preview of the actual size of the brush… you can also try it out! People who publish brush sets on their personal websites need to provide users with previews. This software is able to generate images for every single brush and can also generate the general image from the panel of the thumbnails you have visualized.”
• Download ABRviewer (Requires Windows)
Very similar to AbrViewer. Available for Windows and Mac & Linux users Download ABRView