YouTube

YouTube sometimes gives you an HQ button to switch to a version with higher quality. But not all videos have this button. You can add "&fmt=18" to the URL and most of the time the video is better than the default one. Or you can bookmark (or better drag and drop it on the bookmark toolbar) the following bookmarklet: YouTube-HQ This was done quick and dirty and may stop working tomorrow....

Patton Oswalt (you probably know him from The King of Queens) talks about YouTube: http://youtube.com/watch?v=f5-VUNXl9D4 (I don't know how long this link survives. Maybe the video is long gone when you read this.) UPDATE: Video is gone now. :-(