Dead-Links.Com - Free Broken Link Checker
To check my list on ProxB.Com, I normally do everything manual, so I started checking for a 'dead link checker' in Google.
I found this website; Free dead links checker.
It's a great website and I believe most of the people should run it, just to check if there are offline websites on their website. I'm glad I found this website, so that's my way to give a little bit in return (by promoting it :D)
Have fun with it, and let's hope you don't have to remove too many links :beer: