Sign in downtown Detroit on the Fisher building door: "Caution: Automatic Door  (push to operate)"

Just outside Houston there are two signs about five feet apart:
State correctional facility, do not pick up hitch-hikers. 
Adopt a highway litter control next mile: Boy Scout Den 102

In Rice Lake, WI is a billboard on the side of a local road advertising for "The Butcher Shop". Right behind the sign...a graveyard.

Driving down the road, I noticed some scribblings on the dirty flatbed truck in front of me. Someone had drawn three arrows, Right, left, and down. The right arrow was pointing at the ditch on the side of the road, and read "El-crasho". The down arrow was pointed at the trucks bumper, and read "El-stopo". The left arrow was pointed at the oncoming lane, and read "el-passo". I had coffee coming out of my nose.