WordPress Scroll Popups Plugin
Scroll Popup allows you to slide popups from all four corners of your website. You can choose in which corner you would like the popup to appear and also the direction you would like the popup to slide from. Display just about any type of content within popups: banners, adsense, contact forms, images, videos, shortcodes, newsletter forms, and anything WordPress editor allows.
UPDATES
Version 1.0.2 - June 26, 2015 New Feature: Added the ability to add a background to popups.
Version 1.0.1 - March 29, 2015 Fixed default options not saving
Version 1.0.0 - March 21, 2015 Initial Release