I printed out the tags on my Polaroid Pogo printer and then stuck them around the department, gave the question sheet out and then watched as people whizzed around trying to find the tags and solve the clues. They seemed to have fun.
If you do this though, a note of warning – the glue on the sticky prints seems to get much harder over time. Don’t stick them on any painted surfaces and try to take them off as soon as you can. Otherwise they can be a bit tricky to remove.