Will it boot if the only display available to it is external TV?..

Nice toy, yes. Aka, computer with external input-output devices. You don't even need a USB keyboard, if you get good enough speech-to-text UI; you can just give commands to TV from afar :-)

Oh, and about paranoid people: you could get N900 to guard your home in your absence, if it can listen to many microphones distributed across your house, and when something unexpected happens, speak through the many speakers, to frighten thieves away. Or, if a fire is starting, call the emergency. Smart house, in short...

Thank you. Best wishes.