That would also be great for "communicating" with the idiot tailgating you when are driving the same speed as the huge truck in front of you (something the tailgater clearly has no comprehension of)
"Hang Up & Drive" would be a saved message for sure.
OK, so I know this thread is old, but............
I want my sign to be bigger than 10"x2" , like clear across the rear window of the pickup maybe 48" x 4"

then maybe the twit behind me can really get my message!
J