That's what I'm hunting for as well; have been for the past few days. Something like BlueTwiddler ( http://hewner.com/programming/ ) is pretty much perfect for me, but it was never commercialized. I'm thinking about picking up http://theperegrine.com/ , adding Bluetooth support, and turning it into essentially a chording keyboard for wearable computers. I need something that will let me type on Glass, the Epson Moverio, and my phone with ease. I'm hoping in the next year that I'll be able to ditch non-wearable computers, from an interface perspective (I'll still have them for heavy lifting, of course).