How does your submission match the theme?
My game "attraction" fits the dual purpose theme, because your main power in the game is gravity flipping, which also activates a light in your player. When on the ceiling you are a light, when on the ground you are an ordinary object. If you are a light, you must avoid non-lit lamps. If you are non-lit, you avoid lit lamps. Basic principle, but not always easy. (You will need to download, GameMaker Studio to play get open source I believe).

Third-party resources
GameMaker Studio (Used for game development)
GarageBand (Create background music)
Pixlr (Backgrounds for game)

Contributors
Michael Kane (developer)
Mark Brown (influenced my game)