Do you need to ...
Find out which users are printing what.
Put users into functional groups/classes.
Charge users/groups for printer usage.
Produce reports/charts on printer usage.

Printer Squirrel is an application that monitors print jobs being sent to printers, and sets charges. It is particularly useful in situations where charging for printing needs to occur instantaneously or where a number of individuals or groups are working together using the same equipment but are financially unrelated and thus need to be charged accordingly.
Printer Squirrel records details such as the user who sent the job, job title, printing parameters and the number of pages printed for each print job, and then assigns a charge for the job. Users can be organised into functional groups and usage reports and charts can be produced for each group. Reports on printer usage can also be automatically emailed to group supervisors.