This is really a fantastic piece of software, I highly recommend everyone checking it out if you're into pattern/texture map creation.
“Chief among my pleasures is Filter Forge, which I've been ranting (positively) and raving (voraciously) about ever since it entered my life.”
Resident Enlightenment Manager Linden Lab, makers of virtual world Second Life
“It's a powerful and logical way of creating effects that's relatively easy to learn by seeing how other effects are built. Creating filters from scratch is time-consuming, but for a wider user group, it's a great way to modify already-created effects.”