I made this brush a while back, it’s a combination of a custom alpha and some intense tweaking of brush settings. It makes super clean and sharp creases in one stroke with a falloff so clean, there’s no edge to smooth out. It’s really sped up my workflow.
download here: http://www.erraticimagery.com/extras/ryankittleson_creasebrush.zip
Check out my youtube video of this brush in action:
http://www.youtube.com/watch?v=NDHMvsN3rvs
Let me know what you think. One tip, make the brush a lot bigger than you think you’ll need it to be.