If you’re a web designer or you have to test your web design in different screen resolution size, this is a solution for you. Window Resizer is a plugin for Mozilla Firefox that can help you test your web design in all of the standard monitor resolution size (640×480, 800×600, 1024×768, 1280×800, 1280×1024, 1600×1200 resolutions.) Download free for Firefox.

Link : Download Window Resizer