If you ride a motorcycle with another rider, you may decide that an intercom system would be an excellent way to communicate without constantly shouting. You could buy a purpose-built unit, but what fun would that be? This Instructables article by “Stuffman” shows you how to hook up a bunch of components with (if all the plugs aren’t the same size) a minimal amount of soldering to make your own custom rig.
This setup is basically a creative way to couple two standard Bluetooth headsets to a cheap wired motorcycle intercom unit. Although advertised as “wired,” you can hook up a Bluetooth receiver module to each input, pairing it with your headsets to emulate a purpose-built unit.
As seen in the image below, depending on your intercom unit, you can hook up an iPod or whatever other audio source you have to a third input, letting you and your partner jam out to anything from Primus to NPR.
Stuffman Velcroed the unit together for easier transport, and inserts it into a camera case when riding. He also notes that with all the wires running around this contraption, it’s entirely possible that you’d get hassled if trying to transport this conglomeration by plane. Maybe it would arouse less suspicion disassembled!