(Star Trek)
They are actually legal tender. This is part of the New Zealand tourism office's "100 percent Middle Earth" campaign.
In the 2006 Christmas Special, "The Runaway Bride," the doctor created a diversion by causing an ATM to spit out money. The prop money used in the show were 10-pound notes with David Tennant on them and 20-pound notes with producer Phil Collinson on them. Now the BBC is letting you print out your own.
(Doctor Who)