You know those front-panel/USB plugs to make it easy to disconnect the front panel buttons and lights from the motherboard headers? I had a few laying around, as well as some old motherboards.
I unsoldered one of the 2-port USB headers from the board and soldered it to an extra header plug to give me two internal USB ports.
Here are a few examples. An extra SATA port? Internal WiFi? Or maybe a ReadyBoost drive?
Here is the link to the SATA adaptor I used. My BIOS finds it, found the optical drive connected to it, and booted a CD off it. Windows 7 required no drivers and I can hot-swap HDDs from it. Oh, and it's only $6 shipped. http://cgi.ebay.com/USB-2-0-SATA-Bri...item4cf6f73e94