I've told you before about dangerous places to swipe your credit or debit card. You want to avoid using them at gas stations, restaurants, in stores and online, if you can help it.
Well, add one more place to that list: USPS stamp kiosks.
According to the United States Postal Inspection Service, there have been an increasing number of reports of skimmers - gadgets that steal card information - found on these self-service stamp vending machines. A full investigation is now underway.