I've always admired Mailchimp for their excellent content writing. I watched a great talk by Tom and Rob from @bluegg at the brilliant Port 80 2012 event, about Personality on the Web, where they discussed the importance of tone. I think that talk is what got me even more into collecting funny 404s.
Thing is with 404s is that they get removed and updated, which is why I like collecting them even more. Currently Mailchimp have a cold chimp on an animated background. All very swish as my gran would say.
However, for their previous 404, Mailchimp knew that a long string of sausages is always funny!