I think there was something like a Game Chef revolving around this once, but I don't know if it's been done more recently and I don't remember for sure that it actually worked.
The idea is that you take one or two songs and combine them into a game; the intent is for designers to use a song with lyrics so that they can integrate them, though simply relying on the sound for inspiration is acceptable, if somewhat more difficult. If using multiple songs, they should either be very similar (for instance, two songs by the same artist on the same album addressing the same subject) or rather different (futurepop and classical, for instance).
I might try to do something like this in the next few days, though I haven't yet decided on song selections for inspiration.