Sticky
Sticky is jQuery plugin that fixes block on screen while scrolling. Tipically used for sitebars.
Demo
http://happyproff.ru/jquery-sticky-plugin/
Usage
Inlcude plugin:
<script src="js/jquery.min.js"></script> <script src="js/sticky.jquery.js"></script>
Use it:
$('.sneakyBlock').sticky();
or
$('.sneakyBlock').sticky(50);
(where 50 is distance in pixels between sneakyBlock and top of window)