I installed a USB-related update through Live Update last night and when I
rebooted my computer my mouse & keyboard no longer work.

They light up, and the keyboard works in BIOS so I assume this is a driver
issue.

I've reseated them, switched USB ports, even tried them in the ps2 ports but
nothing seems to work. I've even tried a different mouse & keyboard but I
get the same problem.

I'd love to try re-installing drivers or something, but as I said the mouse
& keyboard don't work so I can't even log in.

Suggestions, anyone?