I have tried 'lpstat' and 'cancel spoolfilename'.
I have tried 'lpq' and 'lprm'
I have tried deleting files in /var/spool/cups and /var/spool/cups/tmp
I have tried turning the printer off and back on

But every time I turn the printer back on, it keeps trying to print a pending print file with a never-ending flow of *blank* pages.

Surely there must be some way to *absolutely* kill pending print jobs. What is the best way to do so?

joe at actionline.com

Turn off the printer. Unplug it's USB, parallel, or network cable (whatever you have connecting it to the computer). Turn the printer back on.

If it starts trying to print again then the job is somehow queued IN THE PRINTER and not in Linux. I would not expect your printer to have this capability, but not knowing your hardware, it certainly could. Especially if it's an expensive multi-user heavy-duty network gadget.

Are there any other queues between where you're trying the 'cancel' command, etc., and the actual printer? i.e., has the job already left your local queue and is sitting in SOME OTHER system's queue? Can you see the job listed in your local queue? After you try a cancel can you verify that the job is no longer listed in your local queue? What triggers the job to reappear in your local queue if in fact it's dissappearing after a cancel commnad?

I've not had any problems using lprm with a dash ( - )

Run 'lpstat -o' to get a list of pending print jobs, then run '/usr/bin/cancel hplj4-01' assuming hplj4-01 is the print job. Make sure you specify /usr/bin/cancel and not cancel, especially with older versions of cups. There is a for loop that I run when I want to cancel all jobs.

the first thing I would do is putting the paper out of the printer...*g

I agree with haertig. But I would add one step. After turning off the printer and unplugging the cable by with the computer communicates with the printer, also unplug the power cord.

Reason: It may be that turning off the printer doesn't completely turn off electrical power to all circuits. Such as, a warming circuit (read standby mode) so that the printer is up and ready quickly after turning power back on. Such standby power may also maintain power to memory circuits which have not been flushed on print job completion (I've had jobs remain in memory even though power was turned off and the parrallel cable disconnected). Only by also unplugging the power cord was I able to completely clear memory and loose the troublesome print job. (Printer this happened on: HP 882C).