If you need to clear your entire print queue in Mac OS X for whatever reason, there is a simple terminal command you can type to do the job.
- Launch Terminal
- Type cancel -a -
All print jobs in the print queue should now be gone!
I have only tested this in Mac OS X 10.5 Leopard. I assume it will work in 10.4 Tiger as well. NOTE: this works for Mountain Lion as well.
This should come in handy should you find your prints are backed up behind a lot of erroneous print jobs.