LinkChecker - LinkChecker is a free, GPL licensed website validator.
Exposely - Immediately reach the largest audiences.
Xenu's Link Sleuth - Xenus Link Sleuth checks Web sites for broken links.
Mustr - Mustr is a public relations platform that helps the media team in organizing the network of journalists and bloggers and maintaining relations with them.
Integrity - Feature comparison of link checkers for Mac: Integrity, Integrity Plus and Scrutiny
Crowdly - Crowdly is a social advocate management platform, helps brands find, rank and engage their top advocates on Facebook.