The TechCrunch Deadpool (<a href="http://www.techcrunch.com/tag/deadpool" rel="nofollow">http://www.techcrunch.com/tag/deadpool</a>) is one place to start.
FuckedCompany.com (<a href="http://www.fuckedcompany.com/index.html" rel="nofollow">http://www.fuckedcompany.com/index.html</a>), though it isn't posting new companies anymore. The author wrote a book called "F'd Companies" that chronicled some of the worst dot-bomb era flameouts.
CNET's list is classic (if that's what you're looking for). It includes such classic one-hit wonders as: Boo.com, Webvan, and Pets.com. It's a good list to learn that spending lots of money quickly on marketing will not make a great idea better.<p>I would also suggest reading: <a href="http://www.inc.com/magazine/20070601/features-how-to-kill-a-great-idea.html" rel="nofollow">http://www.inc.com/magazine/20070601/features-how-to-kill-a-...</a>. It's cool to see how Friendster didn't win in the war for US social networking (even though southeastern Asia loves it).