Wow, this is incredibly well made and a lot of fun!
I think the only thing that bothers me a little bit are the levers. Maybe it's just me, but I thought at first they were relational: So if I put it in the lowest position, the object will be scaled down to a certain point. But they only influence the speed at which something is scaled. I think the game works just as well like that, but I was a little bit confused at the beginning. One other thing: Mapping buttons to the actions of the levers and button would be a great feature I believe (Think W / S for the left lever, arrow up / down for the right one and enter for the button).
Also: Look mom, I'm famous, I'm fourth on the leaderboard!