**This can be done with ANY kind of Pi**

**The least-expensive solution is to use the Pi Zero.**

The text of this link is way too long to post here, but the Zero can be any kind of HID.  Keyboard, mouse, flash drive, camera, whatever you can think of.  

[Turning your Raspberry PI Zero into a USB Gadget][1]

[![enter image description here][2]][2]

Making it a keyboard or mouse is easy.


  [1]: https://learn.adafruit.com/turning-your-raspberry-pi-zero-into-a-usb-gadget?view=all
  [2]: https://i.sstatic.net/l1Uwj.jpg