I don't know if any of you here have ever heard of what I think has to be the two world's greatest chalk artists, men by the names of "Julian Beever" and "Kurt Wenner". If you don't know them, well, forget about their names for now, just concentrate on looking at their incredible, mind blowing drawings which were done on simple color chalks:
http://slodive.com/inspiration/15-awesome-chalk-illustrations-by-julian-beever-and-kurt-wenner/Personal comment: The only thing I regret is not being able to be there in person to look at these drawing marvels with my own eyes. I wonder if CGI can even duplicate something like this and have the same impact.
Never ceases to amaze me.
The last one was amazing. The one with the may pole made me chuckle.
Well, I guess plenty of dedication and lots and lots and lots of chalks.
EDIT: Hey, I just noticed something about the last picture: If you look close to the bottom and a bit to the left of the picture, where the "water" is painted at, and if you look carefully, you can actually make out the outline of the street's manhole cover.