Assuming that they're going for cheap with a good rate of return, I'd be more inclined to go with "screenshots of whatever you watch and when you watch it". Of

Assuming that they're going for cheap with a good rate of return, I'd be more inclined to go with "screenshots of whatever you watch and when you watch it". Of course, you can do all sorts of interesting analysis on this (when is this person home, what hours do they probably work, what demographic do they belong in given what they watch and when they watch it, etc). I don't think you need cutting-edge research based stuff to get some seriously creepy invasion of your privacy.