You know that bluetooth on your phone?
That’s named after this guy:

Harald Bluetooth, King of the Danes, responsible for the Christianization of Denmark, the raising of the Jellinge-stone, and a bunch of other stuff.
The logo for bluetooth is literally his initials written in runes, squished together.

1Keyboard
eyalw.com1Keyboard is a virtual bluetooth keyboard application for OS X. Turn your Mac into a Bluetooth keyboard that works with all of your devices, comfortably type on your iPhone, iPad, Apple TV or game console.