This advertisement ist just wholly awesome.
It is not funny, does not rotate in tv and does not occur in a magazine, it is presented only once to a thousand of visitors and then it is finished. The entire project production lasted 4 months!
Quality over quantity, huh?
After all, this video was published everywhere on the internet and gets thousands of views (views increased from 13.000 to about 20.000 on youtube in the 2 hours and will definitely increase further) so there is a quantity factor, but... Wow!
Actually, there are other companies than Hyundai which also projected some 3D stuff onto buildings, Hot Wheels for example. But actually actually, they had no real car hanging around somewhere in the projection :D
If you want to, check out the making of video of Hyundai's ad down there, too.
I'm sorry about not knowing the advertising agency.. But you could have a look at LLR's website for a second or third time instead, there's much to explore (some content is only available in German) :)