Electronic and Gadget Wizards...BUZZER

[bleeb]

This buzzer will be used to determine who buzzes in first.

1. Must be accurate.
2. REALLY cheap to make.
3. Can add additional buzzers.
4. REALLY cheap to make.

Anyone know how to make one or a cheap system that is already available? I'm pretty dirt poor so this would have to be cheap, basic, but still functional.

 

[mobobuff]

Maybe a little bit of this?

I'm sure something like this could be easily made by someone with enough knowledge in circuitry and where to go for all the parts.