KLinkStatus is a link checker, which was developed as part of the K Desktop Environment (KDE).
It's very easy to use and gets your job done.
Useful configuration options are available and it's possible to use several protocols like sftp, file, ftp, etc.
More advanced features like automation and scripting, fixing links and finding unreferred documents, are being worked on for the KDE 4 release.
These details are provided for information only. No information here is legal advice and should not be used as such.