One of my favorite sources of inspiration is Oblique Strategies, first created by Peter Schmidt and Brian Eno in 1975. It's a set of 103 cards, each bearing a short, cryptic instruction or question, such as "Use 'unqualified' people" or "Go outside. Shut the door" or "Is it finished?"
There are an endless number of ways to use Oblique Strategies, the most obvious being to simply draw a card and see what it inspires you to do. I like using it with groups as a way to introduce some randomness into the experience. Here's a simple game for a group discussion:
1) Deal three cards to each person.
2) Everyone reviews their cards and then keeps one card for themselves, passes one card to the person on their left, and discards the remaining card.
3) Everyone now has two cards, one they chose for themselves and one chosen for them.
4) What do these cards make us think about? Talk to the group about one (or both) of them. (The provocative content of the cards and the framing of a "game" gives people permission to go places they might not otherwise.)
I have the 5th edition of the cards, "slightly revised" in 2001, which you can buy directly from Brian Eno for £30 ($45.33 at today's exchange rate). You can also sometimes find used 5th edition decks on Amazon for a reasonable price, but older editions are insanely expensive collector's items.
There are also Oblique Strategies apps, and while I don't find them as useful as the physical cards, they're certainly more convenient to lug around. A free iOS app is currently available, but I'm told that it always shows the cards in the same order, which defeats the purpose.
Another free iOS app, "Oblique Cards," that shows the cards in random order was developed by Viktor Kelemen, but Apple tells me it's no longer available in the U.S. Too bad.
Photo of Peter Schmidt and Brian Eno © Ritva Saarikko.