AIMster, You can do that with AI, but I'd recommend using a factor of 2 instead 10.
That's essentiall what I do as I use the regular AIM spreadsheet and modified it to keep track of virtual and real stocks and cash. So unlike Steve I have both virtual and real cash as well, and if you use AI you will have both virtual and real cash as well as stocks. Only you know that you're not holding all the stocks and all the cash that AI thinks you have.
The only drawback is you'll have to keep track separately of your real holdings for each stock.