How can an administrator limit clocktime used by a Windows executable per time period?

Question

In lieu of proper parenting, I want to limit the amount of clocktime a Windows executable consumes per time period - for example, I want my child playing no more one hour of Batman per day, without it affecting the amount of time available to run other programs.

We're controlling Internet access via a web proxy; frivolous web sites are permitted within a time-window each day, outside of that only whitelisted sites are accessable. Naturally, with these controls in place now we're seeing more time spent on frivolous local execuatables.

The ecosystem in which this solution needs to work extends from Windows XP upwards, so the solution at "How can I set a time-limit on a batch file?" could be used by wrapping the required programs up in that batch file, but would need to be extended to record when the program was last run. Fairness would also require the recording of execution time, so that a two-minute run doesn't preclude subsequent use. As the user in question is prone to hibernating their computer, awareness of this would be helpful; tying into that would require something more than a batch file.

The are existing products that provide time limits for access to the computer (also, apparently, this one), but not individual programs.

How can I achieve this, other than the above-mentioned some home-brew wrapper?