Demo for stocks?

Where can I find free or inexpensive demo for stocks.
My wife want to try trade stocks and I talk her in trying first on demo but I never was interested in stocks so I virtually know nothing. Can someone point out please where can be open demo account for stocks?

prorealtime.com have just released a new program for people to trade demo accounts. As they offer all the world markets im sure it would be a good program to use. Its a very good charting program. Its not like mt4, how it is offered as live streaming data. This is all end of day stuff unless u wana pay.

Try investopedia.com you can use a great simulator for free (based on real prices), participate in trading games and there is a TON of information. I've been using it for sometime now and really like it. You can also trade options there as well.

Thank you guys.

Wall Street Survivor, though a contest, is really well-done to use for stocks demoing.

Thank you! Any input on this greatly appreciated.