Tracking expenses with Civi
The post can be found here:
https://civicrm.org/blogs/chrischinchilla/using-civicrm-project-management-and-budgeting

The description how the budgeting/expense tracking is done is quite short and it only mentions that they are using negative contributions for expenses. They are also using CiviCampaign to assign the expenses to "projects".

The poster Chinchilla is describing an implementation on Drupal using drupal-views, if you are using wordpress I am trying to collect recommended plugins here: What is the recommended Wordpress equivalent for drupal-views