As a child I would notice the "Road slick when wet signs" (with the wavy lines below the silhouette of the car) and think that it was a warning that this crazy octopus creature could be found on that stretch of road.
A childhood belief about road signs

others believed things like this
- I used to beleive that road signs grew out of the ground.— Tiana
- I believed that the gap between the double yellow lines in the road was a special lane for motorcycles.— Joel
- I used to see "End Road Work" signs, and thought they were a sort of protest.— Sebastian
- I used to believe that the sky had stop lights and road signs floating about for the airplanes.
— LoonaSM's - When I was little, I used to believe that deer could only cross the road at the deer crossing signs. — Shellie
- I used to believe the "Yield" from the road sign was somebody's name.— julia