I presented this technology a while ago (back in the days of Deeply Interesting Friday) and you all thought I was crazy… well now it’s a reality: A Facebook application that scans through photo galleries, automatically detects your face (and your friend’s faces), and ask you if you want to tag them or not.

It can scan ANY public photo gallery, so basically it can find every single public photo of you and friends throughout all of Facebook. If it sees a face, but doesn’t recognise it as one of your friends, it allows you to enter their name.

The app has been in private Beta since March 2009, but they’ve just released public versions of the app, and from a quick test run it is pretty amazing; I’m getting close to 100% accuracy even with some pretty tricky photos.

More info / try it out at www.face.com.

I’m not 100% sure how it works, but I think I’ve got a fair idea… allow me to illustrate: