by James Edwards

Greasemonkey is a Firefox extension by Aaron Boodman, which allows you to run personal DHTML scripts (known as "user scripts") on any Website. User scripts are essentially bookmarklets that run automatically, but because they do, they're a whole lot more useful.

Ever used a site that doesn't work in Firefox, even though it could with just a few minor tweaks? Ever frustrated by a site you really like apart from one annoying thing it does, or felt the desire to customise sites you visit often? Just as user CSS allows you to change the way Websites appear, so user JS allows you change the way Websites behave.