I've set up a standard exp:member:login form for members-only content. My client has requested that I add a checkbox field that would require users to check before they would be allowed to log in. It doesn't appear that the standard login form allows for "rules:" parameters. I've looked around on Devot-ee, and I haven't seen anything that looks like it would fit the bill.
Is there a way to do this using standard EE tags/parameters? Or maybe an add-on that would allow me to add this functionality? If not, do you have suggestions for how I might build this?