YouTubeTime.com makes it easy to link to a specific time in a YouTube video.
Do It Yourself Example
To link to 2 minutes & 14 seconds into this video of dancing in a Microsoft store, http://www.youtube.com/watch?v=TSAXEVXvNz8, add #t=2m14s to the end of the url:
http://www.youtube.com/watch?v=TSAXEVXvNz8#t=2m14s.
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