CAD, or Control-Alt-Delete, is of course pretty obvious. All members of the Clan are Programmers, and as such have a sufficiently sceptic view of the operating system that made this key-combination famous.
A second, less known source for the name, is "Weird Al" Yankovic's song It's all about the Pentiums, which contains the line: Play me online? Well, you know that I'll beat you. If I ever meet you I'll control-alt-delete you.
We thought that a great motto.