What is funny about Shadrack, Meshack, and Abendigo?

I get regular search engine traffic for the term "Shadrack, Meshack, and Abendigo." I can't imagine that I am any type of authority on the three, so my best guess is that I made a common spelling mistake on one of their names. I hope I can expand someone's knowledge out there, but tonight I had a hit from a S, M, & A search that I've not seen before: "Shadrack, Meshack, and Abendigo Jokes." What? What is funny about S, M, & A? I can't think of a funny joke that begins Shadrack, Meshack, and Abendigo walk into a bar...