The recently reported TJ Maxx security breach—where data on 94 million credit card accounts was stolen in 2003, 2004, and 2006—has ended up costing the company $200 million and counting. But although it’s the biggest example so far of retail data theft, TJ Maxx isn’t the only retailer doing a poor job of keeping sensitive data protected from hackers. One wireless security vendor recently surveyed thousands of stores and discovered that a significant number of retailers don’t practice good wireless security: