Do we got a reasonable projection of how much USD wil exist by the time Bitcoins are close to reaching the big 21 mark?
Assuming the federal reserve company still exists and us is still controlled through violence (read "presidency and governments") I believe this is fairly reasonable projection of how many us dollars will exist: us$100,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000.00
At that time it will cost about us$100,000,000,000,000,000,000,000,000,000.00 to order a coffee at a restaurant.