One of those classic little jokes has always been the sign warning the average "non-technieschen peeper" to "Keep your hands in your pockets, relax and watch the Blinkenlights!".
It too has it's WikiPedia page of course.
Another version of the story was later created. "Simplified" for those not proficient in German to this:
This room is fullfilled mit special electronische equippment.
Fingergrabbing and pressing the cnoeppkes from the computers is allowed for die experts only!
So all the "lefthanders" stay away and do not disturben the brainstorming von here working intelligencies.
Otherwise you will be out thrown and kicked anderswhere!
Also: please keep still and only watchen astaunished the blinkenlights.