YouTube allows you to send others to a specific point in a video by appending a short tag to the end of the video's URL.
To specify a point, append a tag to the end of your video link with the following syntax: “#t=1m45s” (you can change the numbers before the ‘m’ and ‘s’ to edit the minutes and seconds, respectively).
Here’s an example:
If I want to send someone a link to a YouTube video, but only want them to see the last minute of that video, I can make the following changes to the URL, so that the 2:24 minute video will start playing 1:24 minutes in.
I strip out everything after (and including) the first ampersand and add #t=1m24s
so, the URL now looks like: http://www.youtube.com/watch?v=ddO9idmax0o#t=1m24s
You can now save this link to your bookmarks, link to it from your website or send it in an email.