Bit.ly for Drupal by Robin Monks <http://robinmonks.com/>

Bit.ly for Drupal, once installed, provides easy access to the bit.ly
API to other Drupal modules and provides a simple statistics page for
site administrators; and, optionally, for each Drupal user.

Short URLs created using bit.ly can also be genorated on each node
by clicking the "Short URL" link in the node links.

IMPORTANT NOTE: This module requires you have a bit.ly account to work
properly, after installation, please go to /admin/settings/bitly to
authenticate and begin using the module.

bitly.inc comes from https://github.com/Falicon/BitlyPHP and is also released
under the GPL.