Rat Race: Plenty of hobbyists have turned their passions into businesses. Take classic cars, for instance, or baseball cards. Hey, take rats. Samantha Martin, a rat lover since age 16, started Scales to Tails, doing business as The Rat Co. & Friends, in Chicago, to give her rodents the showcase they deserve. Her amazing acro-rats -- they jump hoops, they bowl, they fetch mail -- began performing at parties about five years ago for up to $500 a gig. Over the years, Scales to Tails expanded its staff to include other rodents, reptiles, and small exotic and domestic mammals. Martin, the company's "chief executive human," has also added an animal-rental division and a traveling petting zoo. But as often happens, growth has posed management problems: her 80-member menagerie has wreaked havoc on her home. "All my furniture is torn up," she reports. "The prairie dog has nowhere else to burrow."

-- Anne Murphy

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