Asterisk click to call

I use an hosted asterisk service for my telephone system. I would like to have a click to call application that would allow visitors to a website to click a button, enter their phone number and have the script ring both a pre determined number and the number entered by the visitor. If the script can be written in such a way that the call to me is initiated from my server, that call could essentially be a internal extension to extension call which would be free.