My home computer had a print job in the printer queue that would not delete. After searching some Apple forums, I discovered that Apple has been using a standards-based, open source printing system developed by Apple Inc. for Mac OS® X and other UNIX®-like operating systems. It is called CUPS and can be found by typing http://localhost:631/printers/ into any browser.
In OS 10.5 it looks like this.
In OS 10.6, CUPS looks like this:
With this utility, I was able to cancel all jobs. Don’t know why the job was stuck but at least it is no longer clogging the list. Problem solved.