Open Source: YOURLS API now available
What is YOURLS?
YOURLS stands for Your Own URL Shortener. It is a small set of PHP scripts that will allow you to run your own URL shortening service (a la TinyURL or bitly).
Running your own URL shortener is fun, geeky and useful: you own your data and don’t depend on third party services. It’s also a great way to add branding to your short URLs, instead of using the same public URL shortener everyone uses.
YOURLS Homepage: http://yourls.org/