[nicky0]

A useful service to "unshorten" links is http://longurl.org/

Paste in a shortened link and it will tell you the original URL, listing all the intermediate steps on the way. It also has an API.

[cbaleanu]

I couldn't find a working Chrome extension so I created a basic one [1]

[1]: https://github.com/codrineugeniu/chrome-unshortener

[Sir_Cmpwn]

There's no real need for an API. Just do an HTTP HEAD request until you stop getting redirects (watch out for loops).

[stephengillie]

Some days, I go around internetting and it's like I'm lengthening URLs with that page every 5 clicks.