I did! Granted it's an older computer I bought for the business about 5 years ago. I had a USB wireless mouse, a receipt printer, regular printer, and card reader plugged in to rear USB ports and plugged a Samsung USB cord into a front port to flash a phone and boom. Computer locked up.

Messed with it for hours and I was unable to get it to boot up even after a sys restore. Finally I disconnected everything except monitor and rebooted and it came on, but anytime I plug in more than 2 USB ports it locks up again.

Luckily that allowed me to get all my files and programs on an external drive and now I'm waiting on a brand new one with a Core 2 Duo and 3GB of mem!