I hate broken links

I know I am probably asking for too much here but here goes.

We attached videos from Youtube a lot on my site. Images are also attached via a URL to new threads as we require at least one (1) related content type image to every new thread posted. ( I feel the related content image requirement makes for a more interesting reading and members seem to agree with me. )

Question: Is there a way or an addon that would check all messages and replies to look for bad links. Every now and again I find a broken link mostly from Youtube. Of course, this happens if I happen to land on the thread with the broken link. No one ever reports them to us, but I am an ass when it comes to broken links.