Okay, everyone knows you can’t take so much as a nail clipper on an airplane these days — but how about a scorpion? Last month, U.S. Fish and Wildlife Service inspectors in Miami impounded a shipment of 600 of the critters, plus 2,000 reptiles and other invertebrates. That’s a lot of crawly things, but the shipment was just one of untold others that are, well, fishy — or downright illegal. The economy might be sluggish, but the exotic pet trade is booming, and the commodities include chimps, tigers, wolves, bears, tarantulas, and just about every other creature you can’t imagine wanting to own. The legal trade amounts to tens of billions of dollars annually, and Interpol estimates that the black-market counterpart runs to $12 billion per year — second only to drugs. Environmentalists say the real figure is much higher, since the dollar signs don’t reflect the ecological, social, and health cost of extinction, ecosystem disruptions, non-native species invasions, and other woes.