I don’t know how widespread this is, but check out this remarkably creative approach to wayfinding in a parking lot:
In Melbourne I developed a way-finding-system for the Eureka Tower Car Park while working for Emery Studio. The distorted letters on the wall can be read perfectly when standing at the right position.
Very clever, eh?
DarrenBarefoot.com 
Yes, but how do you get to the right position? If the letter are distorted where I am how do I know which way to move?
My friend emailed me a link to some similar effects done more for art.
That site seems to be down… any alternate pointers?
Great views. I saw this on a typography blog a week back or so but the images were not nearly a complete as this. Thanks for the link!