When I add a new contact to my cell/mobile phone, I want it to store when it was added and where I was when I added it (either by phone tower triangulation or gps).
That way, when I meet a girl called Jess and I add her to my phone, then i go to call her a few days later and realise I have 3 Jess's
in my phone, I can figure out which is which. That way I don't have to call the girl I don't want to talk to ever again just to figure out it's the wrong one..
So simple to implement, yet my phone still doesn't do it!