Im trialing Market Tools Prospectus which runs from realtime data sources,Bourse Data and the one I use Marketcast.
So far Im impressed and after using the 30 day trial have paid for it 3 times already.
It DOES have high and low alert capabilities for multiple stocks and live charting for tick and any other timeframe you wish to choose.
Also a portfolio (limited) application.
Has about 100 indicators/ocsillators for those who love to buggerise around,3 types of live charting including point and figure and Candlesticks.
A swing trading feature and Kagi and Renko for the Price action freaks.
Here is a chart with some commentry Im trading today just to show some of the capability off.
If your trading short term seriously this sort of software is a must!!