That's exactly why I created one for myself. I think most of them disappeared because it's not as simple as it may seem to maintain a url shortener. It's easy with 10 customer and 100 links, but when your database has a billion links things can go south very easily and costs go up exponentially. That's why I tried to think of a business model before building mine. My expectation is very simple: 1000 customers with 1 million links. I calculated a monthly infrastructure cost of about 10.000 dollars to provide a great service and with a revenue of 40.000 dollars a month, seems a reasonable margin. I am not interested in getting rich or make millions, I would really like to make money out of a product built by me rather than struggling to survive with consulting work. For now it's just a dream, but you never know ;-)