ideas: the sudden cessation of stupidity

In my line of work, as a copywriter at an advertising agency, it's my job to come up with ideas. Funny ideas, clever ideas, smart ideas, strategic ideas, Earth-shattering ideas. OK, maybe not Earth-shattering ones.

Sometimes, it's not easy. Today, my creative partner, C, and I are taking part in an advertising competition and we will have just 24 hours to come up with an award-winning idea. We work well together as a team, but what happens if all we can come up with are duds? 

Where do you find your creative inspiration?