Charles Mangin from Option8 managed to cram a USB stick into an old floppy in such a way that's just fresh enough to be a DIY project I wouldn't mind attempting myself.
The hack actually involved two disks, cut apart and stacked together. This was done so that the connector could fit snugly inside.
One of the cooler additions is the red indicator light. Manguin popped out the disk's locking write-protect switch and now the red activity light shows through.