You're going to run into a wall called cross site request forgery (xsrf). What your probably going to want to do is make a type of web proxy (something like this already exists though?) that takes the login, scrapes the page, takes more info and scrapes the page, and continues to repeat the process.
Either way, what you're asking about is a directed man in the middle attack. It might be completely legitimate because of the company policy of where your users work or some other law (I can't think of how or why and I doubt this is legitimate). But that should start you on enough resources to do what you want to do.