pop up when user reaches end of article plugin for wordpress

Hi I was looking at plugins for something that will make a popup show up to a user when they finish reading an article and found this one http://scrollcheckpoint.sevenspark.com/ I though it was a great plugin but the author has stopped supporting it in codecanyon So I am trying to find something similar but no luck yet, Anyone know any?

That is pretty awesome, I have seen that used in quite a few places and is very effective in grabbing my attention to stay on the site and read more.