URLShortener is an extension for Google Chrome / Chromium and Opera 15+ which allows you to shorten the current website URL and makes it easy to post to Twitter, also copy to clipboard and see the URL QRcode.
How to use:
Go to the options page you can choose which URL shortener services you would like to use, e.g. BitLy needs you user name and API Key in order to work properly.
It also has an option to retrieve the current website's title and include it along with the shortened URL so it becomes easy to post to twitter without having to write anything.
In order to post to twitter, you need to authorize this extension with oauth by twitter.
- Bit.Ly + history (only 100/day)