Page Canary is an artificially intelligent bot that will navigate your website and report any problems. As Page Canary crawls your site, it will learn how it works and improve efficency of future crawls. Page Canary uses your website like a real user would, helping to uncover issues that directly affect your customers. You can think of it like a robot vacuum cleaner for your website! It is always online and can perform hundreds of checks in seconds.
Here is a video of it in action on wikipedia.com