Yet Another YouTube Script, by eugenox. Unlike nearly every other predecessing YouTube userscripts that erratically worked or broke with site revisions, this userscript interfaces with the YouTube Player API to globally control autoplay and playback quality to stop the repeated web annoyance of YouTube autoplay. (It also lets you pick a lower or higher quality video as your default.) [more inside]
posted by WCityMike on Jul 18, 2010 - 8 comments

Run Firefox with greasemonkey and Facebook Purity to free yourself from the Tyranny of Facebook Quizzes. It's the nuclear option, and it works... like the bomb. BOOM. No more quizzy.
posted by chuckdarwin on Jun 18, 2009 - 72 comments

Gina Trapani's Invisibility Cloak is a GreaseMonkey script for Firefox that blocks time-wasting websites while you're working. Conveniently, MetaFilter is included by default. Previously: Temptation Blocker.
posted by russilwvong on May 16, 2007 - 13 comments

Google Live Search
A Greasemonkey Script that enables you to watch your google results come in live, as you type the search terms. Mesmerizing, time-wasting, and possibly useful.
Greasemonkey and Firefox required.
posted by Edible Energy on Aug 22, 2005 - 32 comments