http://www.filterforge.com/ I saw this post on Unreal developers Network. It would be very useful for Artists looking for a node based texture plugin for making complex textures. It's still in beta, but has a ton of potential!
I normally don't like procedural texture stuff and prefer photo and hand painted. But, this gives you the normal/bump/spec to perfectly match the diffuse, so that seems pretty valuable for the materials that it's able to do well.
http://boards.polycount.net/showflat.php?Cat=0&Number=126084&an=0&page=0#Post126084 I made a couple right off the bat and its quick and fun. I think mixing this with a combination of hand painted you get some incredible stuff.