A barcode scanner
Another simple input device is a barcode scanner. Once again it should look like a usbserial device to Linux. The scanner sends the ASCII text to the BeagleBone, as if it was coming from a keyboard. So now you can scan vehicles, boxes and so on coming into your home or business, using either a barcode or an RFID tag, or both.
All of these devices, with the exception of the geophone, require a USB connection. What I would suggest is a POWERED 4-port USB hub connected to your BeagleBone, and your various sensors and wireless devices connected to it.
Tip
Right now, BeagleBone is powered by a 5V USB.
If you want to connect devices to the USB on the BeagleBone, you should either use a powered USB hub or an external power to the BeagleBone, or both.