I went out into the parking lot behind my res and found five rocks that were all different. I went back to my room and made a character brainstorm for each rock and then figured out how they would all connect together. I started writing the story, although I never did finish it.
I just recently remembered that this happened. It's good to be reminded, sometimes, that when you look for inspiration, you can find it anywhere. If you sit around waiting for it to show up, you'll never get it. I need to go looking.