I was messing around with infinite 302 redirects using the URL shorteners. I set-up the following URL's - http://doiop.com/302_1 redirects to http://doiop.com/302_2 would redirect back to http://doiop.com/302_1
When I tested in Firefox (18.104.22.168), low and behold it detected it!
Firefox has detected that the server is redirecting the request for this address in a way that will never complete.
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Bob Auger from cgisecurity.com helped me test in Internet Explorer 6. The browser just sat there trying to load. Not so smart.