my senior project was an 8051AH-BASIC-controlled home security system, using the $500 Ciarcia-Circuit-Cellar 8051 board, circa 1988. i wrote all the firmware (multi-tasked Basic!) With the team lead and the project adviser at my elbows, i plugged the EPROM power supply line in backward, frying the EPROM programmer circuit (it was a little connector like you see connecting the audio line to a CD-Rom drive, and maybe i wasn't wearing my glasses). after pulling the line, i proceeded to plug in our next-to-last burnt EPROM backward in the PROM socket (it was UV-erasable and it made a pretty little glow). this all left us with no EPROM burner and one programmed EPROM (latest s/w rev. minus 2) to go to final presentation with. i think the lab technician fixed the EPROM burner circuit but i don't remember if it was fixed in time.

james