I quite like Keyhotee, but that's because I pronounce it with an American accent and it actually sounds kinda cool with that accent.

What worries me about that name though is how it'll sound to all the non-english speakers of the world. I just asked my French coworkers to pronounce it, and to them it's kinda hard and does not sound the same..

I think Google in the beginning included a phonetic transcription of their name, if you stick with Keyhotee it would be a good idea to do so as well.

.dac or .bts seem to be good options as they'll also serve as publicity for the bts/dac concepts.

I kinda like .ok myself, not sure if anyones already suggested that. It's short and recognized over most of the world to express agreement, and could be catchy Doesn't look like it's already taken..