Wow, I got quite hooked up! I've had a hard time at the start (even with the tutorial, nice addition btw) but when I knew how to link machines I got absorbed into the game! Seriously, this is a great taken on the tower defense genre! I would love there were more reason to create "products" (right now it's only for the sake of points, I guess?), but it's a great game specially with the 48h limit.