Classic case: all the interesting projects revolve around micro controllers, so you start to dig around and found a dozen of tutorials, how-to’s schematics compilers and so on, you manage to make a simple programmer circuit which is guarantied by some expert from some forum, go out and buy two pieces of atmega8. You have the .hex file, connect the programmer and in that moment your head is full with the data sheet and different settings, you probably remember something about wrong fuse settings could damage the micro controller, and those bits are actually cleared when written, but since you are in a frenzy you click on some fuse settings and load… and then it happens, error reading from device, what could it be, maybe the other IC will work, same fuse settings and load… again the same error.
No more read or write operation, just like the micro controller wouldn’t be attached to the programmer. Most of the thinkers start to measure the supply voltage check the connections and realize at the end that they loaded the wrong fuse settings, and the IC is doomed.
Don’t throw them away in a hurry, you can reset the fuse settings using this parallel high voltage programmer. If you already have the Arduino board this low cost shield can come handy.
AVR fuse rescue with Arduino: [link]