Stock Charting Service With Email Notification on Trendlines

[persistentone]

I realize this is a value investing forum, but there are experienced people here so maybe one of you has seen this feature.  I'm looking for a stock charting service where I can enter trendlines with a slope greater or less than zero that would send an email notification when the stock trades outside that trendline.

 

Many services let you set a support line, which is just a trigger on a single price.  I'm looking for something more complex than that.  I want for example to capture the long term trendline of stocks with predictable future performance, and I want to be notified in X years when some anomolous event happens and the stock trades outside the established trend.

 

I have seen features like this on broker web sites, but a) those require you to stay logged in all the time and b) rarely would they scale to tracking hundreds - or thousands - of securities.  I want a web based service where the trendline lives in the cloud even when I am not logged into the system.