Last June, my friend told me about her plans for our upcoming prom. "I'm renting a stretch limo and spending $1,000 on a new dress, and I've reserved a table at the most expensive restaurant in town," she said. Our teacher overheard her and shook her head. "I didn't spend that much on my wedding." My friend answered, "I can have three or four weddings. But a prom you do only once."