The FBI has posted a $100,000 reward for help in finding who sent identical letters containing what turned out to be a harmless white powder to banking offices across the country. All 50 letters, which were sent between Oct. 17 and 18, were postmarked Amarillo, Texas. FBI today released the text of the letters on its Web site: "STEAL TENS OF THOUSANDS OF PEOPLE'S MONEY AND NOT EXPECT REPERCUSSIONS. IT'S PAYBACK TIME. WHAT YOU JUST BREATHED IN WILL KILL YOU WITHIN 10 DAYS. THANK (Redacted) AND THE FDIC FOR YOUR DEMISE."