UserScripts are site-specific javascript snippets that the browser executes after the page is loaded. It works in the following browsers:

• Safari (with GreaseKit)
• Firefox (with GreaseMonkey)
• Opera

Here’s a list of useful UserScripts:

• HelvetiReader (clean theme for Google Reader)
• immersion (Watch the link’s page in an iframe)
• readelicious (Add to del.icio.us directly from Google Reader)