This is a test of a clock-based timer vs. a framerate based timer. The problem with all my current games is that the timers are clock-based, meaning slower computers are at a disadvantage (ie, the clock keeps running while the computer struggles to render frames). In the future I may use framerate-based counters, so although they wouldn't accurately measure real seconds, they would measure a unit of time that is equivalent on slow or fast computers.
This is the 60fps version which is a lot more demanding than the 30fps version.
If you could post the framerate you're getting at, say, 0, 500, 1000, and 2500 Derpys, (or higher if you'd like) that would be really helpful for me in future game-making endeavors.
Also, try the 30fps version: [link]
Derpy sprite from Desktop Ponies.