David from uC Hobby had a wireless doorbell but the remote was lost, instead of tossing it in the garbage he re-purposed it. By adding a few components to allow a small signal to activate the chime coil this can now be used by almost anything electronic as a cool indication. I would have used it to ding dong when I had a new email but David decided to hook it up to a Linux box to ring whenever someone mentioned uC Hobby on IRC. Goes to show that almost anything can be made even cooler than the original purpose. There is code posted so you too can make your own internet door bell.