Reddit's own investor wanted to name it Octopop. Paul Graham said "Reddit" was poison to investors and told Alexis Ohanian he could turn the little alien into an octopus. Alexis said no. That name now sits on a company worth about $30 billion, and there's a second joke buried in it that most people have never caught. You probably know the first one. Reddit, read it. Alexis has even admitted he's not sure anyone has ever actually said "I read it on Reddit" out loud. The second joke is in what…