[ QUOTE ]
[ QUOTE ]
Off the top of my head, I'd estimate maybe the equivalent of 1 million B-2 bombers.

[/ QUOTE ]

What was this estimate based on other than the top of your head?

[/ QUOTE ]

Nothing. But think about the size of a B-2 bomber and the size of a structure needed for a space elevator. Six degrees of magnitude difference is a fair initial guess.

If you want more exact, say the height needed is 15000k, and a B-2 bomber has a wingspan of about 70m and it takes two B-2's per 70m, thus 15,000,000/70*2 = 430,000 B-2s (within an order of magnitude of my WAG).