Same-sex marriage advocates protest outside the county clerk's office in San Francisco on Feb. 14. Justin Sullivan/Getty Images hide caption

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Building your own stuff boosts your feelings of pride and competence, and also signals to others that you are competent. iStockphoto.com hide caption

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When times are tough, that prehistoric urge to splurge on high-calorie treats like M&Ms still kicks in. Daniel M.N. Turner/NPR hide caption

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Prison provides an opportunity for networking with more seasoned criminals. iStockphoto.com hide caption

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