Infinitely-Draggable-Content is a project mainly written in JavaScript, it's free.
Drag stuff around! For forever and ever!
Dependencies: jQuery 1.4.2 or above, jQuery UI 1.8 (Draggable) or above
Description: This plugin takes some content and makes it draggable to infinite bounds within a constrained area. It works much like the draggable map in Google Maps.
Instructions: Simply call '$().infidrag()' on whatever element you want to make draggable. Define the bounds with options 'height' and 'width.' Here's an example:
$('#content').infiDrag({ height: 400, width: 600 });
Tested on IE 7 and 8, Firefox, Chrome and Safari.