I have a set of teflon-coated mechanic's picks. They're several pointed picks (with bends at various angles) with a hefty handle to make it easy to pull on. The one with a bend at nearly 90 degrees worked best for me on the seals behind timing belt's three gears.

The reason that I particularly liked the teflon coating is that it made it harder to scratch or scuff the surface of the shafts and the seal carrier as I twisted the seals out -- you don't want to scratch those surfaces, as it makes a good, long-lasting seal less successful.