I had just enough time, as I went through the light, to get a glance at the cardboard sign he held.
time traveler needs $ for a new flux capacitor
I haven't seen that particular sign before, but I've seen others like it.
And that day I said to myself: imagine if it was true.
I find I get a lot of ideas at random moments, in random places, inspired by increasingly random things: the way someone walks, a sentence on a billboard, a holiday window display.
Many of them may never see the light of day. But they do a fine job of shoring up my morgue file and every now and then I have one that sticks with me until it develops into something resembling a story.
What's the most interesting thing (event, person, object) that's sparked an idea where you least expect it?