print pop-up message generator

[Gary Giannelli]

We'd like to gently remind partons of the cost the library is incurring
when they print items from the public stations.  I'd like to install
software that, whenever a patron hits the print button, pops a message on
the screen that says something to the effect "You are about to print x
number of pages, blah blah..."  The idea is to make them think twice about
frivolous printing.

I know such software exists.  Where?

The stations are windows 98; installed software includes winu. 
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Gary Giannelli
Director of MIS
Ferguson Library
One Public Library Plaza
Stamford, CT 06904
gary at fergusonlibrary.org
203-964-1000 x 270; fax 203-357-9098