It's called Mouse Gestures

There are many more actually, you can see them all here:
http://www.opera.com/browser/tutorials/gestures/
I use almost all of them, it's very useful.







(e.g.: people making double posts for sending more than 4 pictures)


We also have a server that takes up the size of a small car, yet does nothing other than the same as a couple of 20-port switches 

