"Do you know what our greatest corporate expense is?" Sergey asked at TGIF. The assembled Googlers looked up from their laptops. Everyone wanted the chance to be right in front of others.

"Health insurance!" shouted an engineer. "Salaries!" "Servers!" "Taxes!"

"Electricity!" "Charlie's grocery bills!" rejoined others.

"No," said Sergey, shaking his head solemnly. "Opportunity cost."