I want to edit an old question of mine with a youtube link. For reference I want to add this link to start at 3:08.
Youtube offers very simple functionality to do this.
Click on the Share option on Youtube, and you are provided with the URL and a couple of boxes underneath to allow you to link directly to the desired timestamp. You can very easily do it manually though:
For example this video URL:
Becomes this URL when I start at 2m14s