Here's the progress so far on my LD47 game. The idea was basically a "create your own Rube Goldberg machine". That was probably a little too much for a 48 hour game jam, but I did manage to have it so that you can create a track for balls to move through. You have a limited number of pieces you can use. Zip pieces give your balls more forward momentum. The objective is to complete the specified number of loops with your balls, which goes back to the theme "stuck in a loop".