Since most people unfortunately do not have paddle controllers for their computers, the motion of the catch buckets is determined by the side-to-side motion of the mouse. The only other input required is for starting, pausing, and reseting the game. All of these functions are provided by the escape key.
I have improved my core code and the game should now run on recent versions of Internet Explorer (IE9, which is not available for Windows XP, only Windows Vista and Windows 7). However, I do this for fun and I use a MacBook. Finding a Windows PC to test code on is more like work than fun, so my program could have some shortcomings in this regard.
As always, enjoy!