Today is Equal Pay Day , which symbolizes how many weeks into 2011 women must work simply to match what men made in 2010. It’s a stunning pay gap, but there’s a growing class of workers whose conditions are even more outrageous: part-timers. The great recession has forced millions of full-time workers to accept the second-class status of lower pay and near-zero benefits. Indeed, involuntary part-time employment has doubled in the past five years to 8.4 million, while the total number of part-timer workers has swollen to 27 million. Yet for all we hear about their plight, they might as well be...