An anonymous reader writes: Security researcher Graham Cluley says he has been forwarded a blackmail letter, sent to a member of the controversial Ashley Madison adultery website. In the letter the blackmailer says that unless $2,000 worth of bitcoin is paid within 10 days, the recipient's wife, friends and colleagues will be informed of his misdemeanors. In a threatening twist, the letter goes on to give personal details of another victim who refused to pay the blackmailers, and how his personal life and work were targeted as a result. Cluley's advice to recipients is not to pay the blackmailers, but to tell the U.S. Postal Inspectors Service.