You'll probably recognise bitly links. But have you got a bitly account? The brilliant thing about bitly, in my opinion, is not so much the shortener but the free analytics are great. You can sit and watch as the links you share get shared and clicked. And once you have "bitlyed"(?) a url, you can see summary activity of other people's bitlys to the exact same url. Its not perfect but its pretty damn useful.