TubeChop is a free web service which allows you to select a specific portion of any YouTube video, and publish it as such.
How does it work? You simply input the URL of the video you want to "cut" or a keyword to search for any video matching your query.
Once you have loaded your chosen video you can manually select exactly the part of the video that you want to "chop out" and once you click the button "Update", you are immediately provided with a link and an embed code to share your excerpted video selection with anyone.
Very useful. 8/10.
Try it out now: http://www.tubechop.com/
(Reviewed by Robin Good)