A computer from which application support staff may administer a limited number of functions in otherwise secured-away areas of a network, for example, a secure DMZ. It is normally "firewalled away" from the bulk of available activities and access is given to the secured areas selectively on an as-needed basis. The origin of "campers" in this context comes from imagining a large "No Camping" sign placed at the edge of the secured area. Camping is allowed, nay, even encouraged, on the Campers Box.
Dave: There's a production problem, and I can't get to "Sausage".
Al: You're doing it form your desktop mate, you should be accessing it from the Campers Box.