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A few years ago, I learned a painful lesson about what not to wear while sightseeing in the summer. As part of my unofficial tour guide uniform for a friend's visit, I slipped into a pair of old Reef flip-flops. I misinterpreted the deep indentations (classic indications of overuse) as signs that they'd been comfortably broken in by a jungle trek in Thailand and a day of beach hopping around Nantucket. I figured they were the best things to wear to walk around town (what are flip-flops but topless sneakers, right?). That night, a throbbing pain in my right ankle kept waking me up. A podiatrist later diagnosed the pain as Achilles tendinitis, and recommended that I wear a soft cast...until Labor Day! My summer was officially a flop.