CD-ROM drive != cup holder. Nuff said.
(No, I've never known anyone to actually do this, but I'm sure some of the stories are true).
My uncle was firmly convinced however, that the McAfee software which came pre-installed on his PC was a virus he got from browsing the internet because it kept popping up warning messages at him, and he wanted me to remove it. It took at least 30 minutes to explain that, no, that software is protecting you from viruses.