We’ve build our very own service for shrinking long URLs. We did that because we can and because we wanted to use our application instead of others’. We’ll most likely be the only ones to use it, although we’re not sure that nobody will actually mind using it 
So, check it out http://go.scripty.ro!
For example this post’s link is converted from http://blog.scriptyweb.com/go-our-own-tinyurlcom/ to http://go.surl.ro/b