I just set up an account with BudURL. Like some similar services it takes a long URL and shortens it.
The twist with BudURL is that is includes analytics behind each link that you create. So, for example, you could include a BudURL link in a Twitter Tweet and then see analytics on any clicks on that link.
I will post more when I have examples of the analytics.
BudURL includes free and paid services based on the number of links you create.