Google Chrome extensions

So what are your favourites or best in your opinion? 
Here are mine: 
AdBlock (it even blocks youtube ads!) - 5 out of 5 
AutoHD for Youtube - 3 out of  5 
Autoplayer for Mafia Wars - 2 out of  5 (does almost nothing)
ChromeAccess - 4  out of  5 
Chromed Bird - 5  out of  5 (get your tweets and post your own)  
Docs PDF/PowerPoint Viewer -  5 out of 5 
RSS subscription - 3 out of 5 
facebook AdBlock - 5 out of 5 
Fast Youtube search - 5 out of 5 
Fastest Chrome - 5 out of 5 
ForecastFox Weather - 4 out of 5 (it can be innacurate) 
Google Quick Scroll - 5 out of 5 (get me to the good stuff) 
Google Share Button - 4 out of 5 
JoinTabs -  5 out of 5 (merge poppers, merge!) 
One Number - 5 out of 5 (Gmail+Wave+Reader+Voice in one and tells me when I have new mails or blog posts to read) 
TinEye Reverse Image search - 5 out of 5 (I want this image in a bigger size) 
Translation bar - 4 out of 5 (some innacuracy) 
Turn off the lights - 5 out of 5 (I just want to focus on the video/photo) 
Webmail Adblocker - 5 out of 5 (no more ads on my Gmail and Yahoo) 
Wikipedia Companion - 4 out of 5 
Youtube HTML5 autoplayer - 4 out of 5 
Youtube. themed. - 5 out of 5