Millions in a trillion?

This video clip reminds me of an anecdote related in The Universe and the Teacup:

[A professor] likes to impress his students with the power of large numbers by drawing a line designating zero at one end of the blackboard and another marking a trillion on the far side.  Then he asks a volunteer to draw a line where a billion would fall.  Most people put it about a third of the way between zero and a trillion, he says.  Actually, it falls very near the chalk line that marks zero.

How Many Millions are in a Trillion? from Econ4U on Vimeo.