This is a super simple, no frills URL shortner.

Set a username and password in config/credentials.yml.

If you're not running this on heroku (works a treat on their free plan, with the free mongo HQ add on), then you'll need to configure it with your mongo db settings.

Fire up the app and head to /links. Enter the username/password you set. 
Create a link with a title of 'default'. This will be the default url that the app will redirect to if no url slug is provided. For example,

http://myshortner.com/fR5 will take you to the link you created with the title fR5.
http://myshortner.com will take you to the link you created with the title 'default' - the, um,  default url, I guess.

Visits for each slug are tracked, and shown on the links page. (I did really mean no frills..)

That's it! If you make it better, which won't be hard, I'll be happy to merge in changes.