My game is a puzzle platformer. You have a short time limit. Once time runs out, the level is reset and you are sent back to the start, but a time clone is added that repeats the actions of your previous self. The time clones can press switches.

There are probably already games like that. I played Braid and a Flash game called The Company of Myself that use similar (but not absolutely identical) mechanics. The game is specifically based on a dream I had some time ago (that was probably influenced by my memories of these games). Anyway, it's too late to start over, so I'll keep going with this idea even if it's not 100% original.