There are a lot of services out there that convert URLs into short URLs. TinyUrl is probably the best known of these services. While these services provide a great service they hide the final location that you are going to. People can use these services to send you to sites that you might not want to go to, especially if you are at work.

LongURL solves this problem. You can go to their site and enter your tiny URL (it works for all of the services out there that create short URLs) and they'll tell you the final location that this tiny URL will send you to. That way you can know where you are going before you go there.