My suggestion is to turn it into art. Keychains have been done before. Go for something unique. Here are some ideas:
1. Futuristic Mousepad: Take 1 chip, place an LED behind it, place a "digital/futuristic" patterned looking backdrop behind that, and encase the whole thing in plexiglass.
2. Pentium³: Take 6 of those and mold them into the shape of a cube. Add LED's inside for added effect, or make it float and spin
3. Go crazy! Get a large 5 x 9 board or tag board or some other board, some unshielded fiber-optic wire, and a bunch of colored LED's. Put all the chips around the surface, maybe in some cool pattern that is also mathematical. Run the fiber wires around, maybe running from chip to chip. Hook some LED's up to the end of each fiber, maybe settled behind the chips, etc... Eventually you'll have some massive pentium digital wall art deco thing that looks cool.