I'm looking for a Joomla 3 extension that requests new visitors to create an account in my site with a Popup. I'd like to offer an e-book in exchange, so the popup should have an area to show how the e-book looks like and another area to register (or login, if the user already has an account). If possible, this extension should also allow users to register/login using FB or Google.
I've seen many extensions but none that does exactly this.
Can someone please advise?