Really, what can't you do on Facebook at this point? A new app from Eric Cantor allows you to "cosponsor" any House bill you want (even if it was introduced by a Democrat), which basically means you declare your support and then can easily track the legislation (you're sent Facebook notifications for bills you support). The House majority leader launched the app and Cosponsor.gov, a Facebook-based website, today, Mashable reports. Unfortunately, there's no way to show you don't approve of a particular bill, or suggest changes to legislation. (More Facebook stories.)