Here's a battlemat of a Bandit Camp I made for my weekly D&D group. Thanks to everyone that offered advice from the WIP thread here:
http://www.cartographersguild.com/showthread.php?t=1749
This was completely done in Photoshop with a lot a lot a lot of layers and quite a few masks. The final was printed to two sheets of 13"x19".
*edit* added a version without a grid