Barack Obama calls them the Propeller-Heads, the cheerful band of financial nerds he has charged with saving America’s economy. And on the Friday before Presidents’ Day weekend, they were ready to show him the latest piece of their rescue plan: the 2010 federal budget. Having just squeezed through Congress what may be the largest spending bill in history, the President now needed to do something that would make the stimulus fight look easy: show the country and the world that he was as serious about preventing waste as he was about promoting growth