The other day somebody asked me if there was a way to run a scan and only see results from his watchlists.  There was not, but after discussing it for a while I saw how it could be useful to those who like to trade from a specific set of stocks.   

So I've now added the ability to run scans against just the stocks which are in your watchlists and portfolios.  Just check the box next to "Only My Stocks" in the form where you enter your scan criteria.