On the back of Paul Hammond's deeply passive personalisation work on the new BBCi homepage, i've been pondering ways of identifying people online or on iTV with low levels of certainty within a very small user group such as a family.

i.e. Is it mum, dad, bro' or sis' picking up the remote / swiping the mouse?

Rather than focus on physical attributes (Alice Taylor's fingerprint scanner in the remote control idea, etc.) or username/pwd key pairs etc, I've been wondering if any of the activities one performs as a normal part of surfing the web / the TV could act as a some kind probablilistic identifier within a very small (family) user group

Some thoughts thus far:

• acceleration of mouse from a standing start
  
• average mouse overshootiness before a click
  
• gap between double clicks
  
• preferred first channel to watch on TV
  
• length of time keys on the remote are depressed
  
• liklihood that volume is increased / decreased
  

All of these are hard to measure, but something like this could make all the difference - particularly on iTV.