I put a USB port in a wireless mouse and I can go to the other side of the room, plug ina flash drive, and it still works
I probly should have done it on the keyboard.. that would have been more practical.. but oh well, Mouse came apart with 2 screws, keyboard had 10 lol
I also did a really primative mod to a computer case once, It sat over an air vent on the floor, So I cut a hole in the bottom of it and installed a filter, so it blew cold air right inside. Didn't look bad either, looked trashy inside but performance was suprisingly better