I built Site Spy after missing a visa appointment slot because a government page changed and I didn’t notice for two weeks.It watches webpages for changes and shows the result like a diff. The part I think HN might find interesting is that it can monitor a specific element on a page, not just the whole page, and it can expose changes as RSS feeds.So instead of tracking an entire noisy page, you can watch just a price, a stock... [原文链接]
