Chip Tower

I mentioned about Coin Castle in my previous post. I always knew that such an idea existed, but I've never tried it out before. Yesterday I had the curiosity to build 1 Chip Tower using the same principle behind the construction of the Coin Castle.
I never thought that it was that easy to build one. With approximately 200 poker chips and 45minutes, I managed to build something like:

Behold, The art of construction....Guys and girls, isn't engineering fun??

I think the construction of a huge gigantic coin tower as big as a 1-story building is actually possible.
Question is: How much worth of coin value is needed to build 1???