Well, I did learn a lot today!
You may be familiar with the restrictions that Windows Vista X64 places on unsigned kernel-mode drivers (I was only vaguely familiar with it). This is new - XP64 (which I upgraded from) would warn but allow installation, from memory - WV64, the driver won't load.
There was a driver for a USB device that I absolutely, positively had to have working, so I looked around for ideas on how to approach it.
Here's the step-by-step guide. Useful for testing while developing a driver, or in situations of dire need.