[Joe's] wife grew up playing Sega games and he wanted to help her unwind by reliving the experience. Since the work computer she uses when travelling isn’t a good place to install emulators he built this plug-and-play emulator inside of a Sega controller.
We’ve seen this type of thing a few times before (even with XBMC in a SNES controller) but there is one thing we hadn’t thought of lately. Newer versions of Windows have auto-launch disabled for USB drives. But [Joe] knew that there were still some USB sticks that manage to auto-launch anyway so he researched how those work. It turns out that they have two partitions, one is formatted as a CDFS which looks like a CD-ROM to Windows and allows auto-launch. He used this method of partitioning a USB stick, storing the ROMs on the mass storage partition and the emulator and the CDFS partition. To finish the hack he cracked open the controller and found room for a USB hub and the PCB from the thumb drive.
If you still have cartridges lying around you can pull the ROMs off of them over USB.