Recommendations for link checking software

I'm seeking recommendations for link checking software. A client I'm working with is currently using Parasoft's WebKing, a robust testing suite that is complete overkill for checking links.

I like the W3C's LinkChecker, but it doesn't keep a cache of which pages it has already checked, and would end up checking the same links 1000 times over.

I'm looking for something that checks links to both internal and external pages.

Thanks!