I was thinking NFC tag-to-watch to trigger limited-interaction sorts of prompts on the phone and then bluetooth from the watch to the phone for relaying the ind

I was thinking NFC tag-to-watch to trigger limited-interaction sorts of prompts on the phone and then bluetooth from the watch to the phone for relaying the indicated data or firing actions or whatever. (bump watches, each watch gets a 'send contact' prompt, watches broker a bluetooth contact card transfer from respective phones) And as for the computer/lock thing, I was thinking Bluetooth. Someone might have to rig up a custom profile for it, but they'd have to do OS integration and awareness anyway. So it's not so much more a roadblock.