Turn Nanny
My kids used to argue and fight over having turns on our computer. So I wrote a little app that would keep track of whose turn it was. After a few weeks of using the application the kids stopped fighting and would willingly change turns.
A few of my fellow parents saw the program and said that they would love to have the same application for their kids. So I decided to develop Turn Nanny a little bit more and release to the public.
I can’t promise your kids will no longer fight over the PC, but it will cut down on the arguments. Best of all my wife and I no longer have to keep track of how long each child has been on the pc.
I have put advertisements into the application to help keep it free to use.