One of my favorite photo subjects is sign errors. Here's an example I just found last weekend near Kansas City, Missouri. Can you spot the obvious difference between the first and second signs for Route 269?
The difference? The first sign shows the highway as US 269 while the second shows it as MO 269. Of course, I'm sure this is something only a "road scholar" would notice ;) .
For trivia buffs, MO 269 is actually an older alignment of US 69 and there is no such highway as US 269 anywhere.