Paul Arden yells this at lectures - "Get out of advertising!" - meaning seek inspiration from outside of the office walls. Some solve this by going to art galleries, others go fishing - I used to go to joke shops a lot and it seems, so do adkids today. It is still one of the best places to seek inspiration, at the very least you'll come home with a bag of "raucher-schnee" to prep your still smoking co-workers cigarettes with causing much mirth when snow falls from their smoke.
I was reminded of the joke shops the forum about this years the Epica results as the direct winner from Leo Burnett Frankfurt were pacifiers with teeth on them were the funny, much like the classic joke item Billy Bobs pacifiers, a whole brand in itself.
Then as I shopped in my favorite jokes&junk stores I found a bag with teeth at the holes, much like the stop nail-biting "stop and grow" bag which was all over Adland in 2006.
I'm sure there are countless more examples. Seems I'm not the only one to find gag gifts the best creative juice out there, so I'm asking you dear adgrunt, where do you get inspired?