LinkChecker - LinkChecker is a free, GPL licensed website validator.
Visualping - Visualping is the easiest to use website checker, webpage change monitoring, website change detector and website change alert software of the web. Read more about Visualping.
DRKSpiderJava - DRKSpider is an open source website crawler (sitemap generator) and link checker. Features:
Distill Web Monitor - Distill is a web monitoring tool. It can monitor RSS feeds, a webpage or a part of webpage. Alerts in the form of pop-up, audio or emails can be received.
Pulno - SEO Audit and Website Analysis. Pull up your SEO.
Update Scanner - Update Scanner is a Firefox extension to monitor web pages for updates.