Ensuring that cited web sources remain stable over time is an important issue for anyone who undertakes research. As such, I wanted to add to a tip I posted a little over a year ago, which listed several strategies for dealing with broken hyperlinks.
Several new developments/resources since that time:
1. Internet Archive: The New Yorker published a very interesting article recently called "Cobweb: Can the Internet be Archived?". (So far, it's still freely available in full-text, but may not be for much longer.) Also recently published is an article on the Global Investigative Journalism Network site that reminds readers to make use of the Internet Archive's "Save Page Now" feature.
2. Hiberlink project: The aim of this project is to investigate the extent of "reference rot" on the web as well as research possible pro-active solutions for archiving web resources that have been cited in scholarly works. Check out their PLOS One article on "Scholarly Context Not Found: One in Five Articles Suffers from Reference Rot" and their web site for more information.
3. Linking "best practices": The Journalist's Resource has put together an extensive list of things to consider when creating hyperlinks to online content. In other words, think before you link!