Pause, rewind and resume the movement of circles, in order to accumulate 10 seconds of *forward* movement among them. That is, if a circle goes forward, it adds time, if it goes backward, it subtracts time. Circles stop when they collide with each other.

Click on a circle: pause/rewind/resume (depending on the icon on it).
Right click: rewind (when possible).

Update (2013-09-05): Added binaries for Android (.apk) and Linux. The Linux build is untested, I used the Unity export and crossed my fingers. Let me know if it works, if you try it. Also, the Android version has no right-click, but it's solvable still, just a bit more awkward.