Earlier this month I talked about the Microchip PIC16C745 and PIC16C765, which are 8-bit microcontrollers with built-in low-speed USB. Since that time, I've got hold of one of these devices and built a simple USB peripheral with it. Click on the thumbnail for a bigger version of the image.
Summary: hardware easy, firmware tricky, software painful. Read on for more detail and some hints for anyone treading the same road in the future.
[Last updated 20050606: added firmware source code.]