In case you haven't heard the news, google bought out youtube this week, and word is that they're going to be clamping down on copyright infringing videos on the site as a result (you knew it had to happen sometime).
So anyway, if there are some Police clips there that you really enjoyed, save 'em while you can, because who knows how long until they're pulled. I've found TubeSock is a great Mac application for doing this.