I thought others here might find this site useful. All that is required is an internet connection and Microsoft Silverlight (a 1 min download). It provides real time data for US markets, and 15 min delay on Canadian stocks.
It has many time intervals, and hundreds of indicators to plot. It updates automatically without any required refreshing. In addition, one can develop and monitor their own portfolio. I've been using it for the last week or so and compared it to my paid service, and conclude that it's very good for a free service. I haven't used the scan feature yet, but it's capable of scanning the markets for your indicator set-up.
http://www.freestockcharts.com/
Good luck,
Booster