A high-tech computer system that captures images of “every mail piece that is processed” by the United State Postal Service was critical in helping federal agents track the Texas woman arrested today for allegedly sending ricin-tainted letters to President Barack Obama and New York City Mayor Michael Bloomberg. In a U.S. District Court complaint filed today against Shannon Guess Richardson, an FBI agent details how investigators traced the ricin letters back to New Boston, Texas, where the 35-year-old Richardson (seen below) lives with her husband.