UserScripts
Install Greasemonkey /
Install Tampermonkey
Display all video playlink IDs found on a youtube page, in an easy to copy/paste box at the bottom of the page.
http://xixs.com/GreaseMonkey/youtubelinks.user.js / http://userscripts.org/scripts/review/33957
EyeCrosser by Kohaku - Puts the chat on the left and tv on the right.
http://esantirulod.appspot.com/data/153001/EyeCrosser.user.js
(The script has been tested for both Greasemonkey and Tampermonkey.)
Zelly's WetGenes Blocker by Zelly - Hides chat from specified users.
https://userscripts.org/scripts/review/153853