> Coca-Cola's market cap is about $150bn. Its price is
> about $60. In extremis, if I placed an order to buy a
> *single share* of Coke at $90 (ignoring practical problems),
> Coke's market cap would rise by a total of $50 billion.
I think you mean $75B :-) [a rise of 50%]
Alas: a microsecond later, their Market Cap would plunge nearly 34%.
/jordan