Sliding notification looks good and also make a good impression on visitors. SlideNote is a nice Jquery plugin which is easy to use and customize. You can easily modify the script to meet your requirement and match with your website look. You can also specify how far down the user must scroll before the notification slides into view. With this script, you will be able to fire the notification once the user scrolls to a certain point on the page.
SlideNote is compatible with jQuery 1.4.3 and current versions of major browsers. Slide Note is compatible with Chrome, Firefox, Safari, Opera, and IE9. Although the plugin works in IE8 but is not officially supported.
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Backbone.Notifier – Flexible UI Notifications Framework