Just wondering, what are some of your favorite brushes, and where can i find some good free brushes/filters.

I try to stay away from using other people's brushes because many times when you uses free brushes out there your art/designs can start to look like other people's work, especially if they are popular brushes. I would suggest that you make your own. It is very easy to do and that way you have much more creative freedom. All you need to do is draw or find whatever you want the brush to be, turn it to grayscale, make a selection in the shpe you want the brush to be, then go to Edit > Define brush. Give you brush a name and it should appear at the bottom of your brush list. It is really simple, yet very powerful.