I'm amassing a pretty large collection of brushes and searching through them 
for a single brush is getting to be a hassle when I need something specific. I 
propose that the brush dialog, along with the pattern and gradient dialogs, be 
given a way to narrow the search. Displaying only the root directory of the 
resource at first, and listing the subdirectories would be fine. Maybe a drop 
down menu above the brushes, something like: 
All Brushes 
- Blood Splats 
- Grunge 
- Shapes