I did some more sleuthing based on a user request. She reported the inability to reach doodle.com. I couldn't find any reason why that site was blocked, so I did a WHOIS lookup. It's based in Ireland. I had blocked Ireland in our firewall. Turns out, if you block Ireland in your firewall, you can't reach cisco.com. This also breaks facebook.com and the aforementioned doodle.com. I removed the Ireland block from the firewall, and all is right with the world again.
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