Anthony Ward has all but cornered the market in cocoa.

Mr. Ward has placed a $1 billion dollar bet in the London market for cocoa futures, buying 241,100 metric tons of beans in July. He controls 7% of the market, enough to sway prices.
Cocoa Trade Associations are upset.

His firm, Armajaro, manages $1.5 billion in assets, and is the world's largest supplier of cocoa. Cocoa prices are up 150% since 2008.

Since cocoa amounts to only 10 percent of the cost of an ordinary chocolate bar such as Cadbury's, etc., ordinary chocoholics needn't worry too much.
"One Trader's Binge on Cocoa Wraps Up Chocolate Market," Julia Werdigier & Julie Creswell, NY Times, July 25, 2010.