The real value add here would be an explanation of each piece of legislation. Merely knowing the aye or nay vote isn't very useful without understanding what the resolution is actually doing, and it's usually not obvious to the untrained reader.

> know how your congressman votes on each of the vote

Actually, the opposite may be a better way.

Our representatives votes should be secret for the same reason that the people votes is secret: prevents the voter from being intimidated and from selling his/her vote.

It would make a great plugin for national news sites, though their internal software teams could build this feature pretty quickly themselves.