Qtechknow writes:

Since youve gotten into electronics, havent you wondered if there is a fart sensor out there?  I sure did.  I discovered that if you use a methane sensor, especially the MQ-5, even at very low concentrations, it reads farts.  What if you combined that into a hat with an LED Bar Graph and a XBee?  Exactly.  The Gas Cap was made with that in mind.  For around $100, you can build your own Gas Cap, a human gas-operated LED Bar Graph on a hat.  So, you fart into the methane sensor, wirelessly transmit that data to the hat, and watch the LEDs light up so that your friends can see how horrible it was.