Creating feeder site with newsletter function for customers

I am looking for a website like [login to view URL] which is a bit like the <[login to view URL]> media / rss feed monitoring system (but then simplified and without the rich analytical tools) with the option for customers to get the latest interesting news items in a newsletter automatically. Other example is: <[login to view URL]> So with login for customer and option to select keywords in which results should be shown. The system should search in RSS feeds / online / Twitter which can be added by me as well as by customers.