My entered instructable for the Duct Tape contest. A nice cover for your Gameboy Advance SP. You can use any color or pattern you want, it doesn't take much tape to cover it.

Materials:
-exacto knife
-roll of duck tape (digital camo for me)

Step 1: Covering Your Gameboy

Cut pieces of tape that are long enough to wrap around the gameboy completely.
Wrap the tape so that the edges are in the back and it looks seamless.
Start around the screen, putting the edge of the tape to the edge of the screen on all four sides, framing it out.
Cut out any pieces you need to cover the all plastic! Only leave the L + R buttons, screen, and game slot exposed. You can cover the A, B, C pad, start, and select buttons. When you are finished, press down on the buttons you are going to cut out, the tape should be pressed in the shape of the button. Now, cut around this line with the exacto knife. You really only need to cut out the C pad and A and B buttons. You should also cut out the charger and link cable ports. Don't force the knife too hard, as it can break the tip off inside the gameboy.

Finished! Now where did I leave that?