According to 2006 Bluetooth Hall of Fame inductee Jim Kardach, Bluetooth comes from the name of an ancient Danish king who went by the moniker Harald Bluetooth. And no, King B wasn't actually Papa Smurf in disguise; legend has it the dude just really loved blueberries and got his name because of his ever-so-sexy fruit-stained teeth.
What's significant about King Bluetooth, though, is that he united different regions and allowed them to communicate with each other. See where this is going?
Despite marketing experts' best efforts to come up with a replacement name for Bluetooth, nothing else stuck.
(Pictured: King Harald's runestone)