You just got a really nice, but not super fancy knife, a Delica for example, and you want to jazz it up a little. What do you do? How about order up some custom scales? Here are a few great spots:
Cuscadi: They have, by far, the largest custom scale operation out there. I have never ordered anything from them but they have been referenced positively on the knife forums. They can make scales for dozens of models, Benchmades, Spydercos, Bokers, and Striders. They also have dozens of different materials, including carbon fiber and a lot of high end hardwoods.
Kevin Wilkins: He makes scales for three models: the Mini Grip, the full sized Grip, and the production LeafStorm. It seems that the LeafStorm scales are out of production. You can buy them from Wilkins himself.
Philip Dobson: This guy is definitely not as well known as the other two, but not for a lack of quality. He uses a bunch of different materials, but it is his wooden scales that are the most amazing. Check out the custom cocobolo scales on this XM-18:
That has got to be one of the most beautiful knives I have ever seen.