This month, like every month, Kip Kohn paid the Long Island Power Authority bill for his Oakdale sporting goods store. And like most months, he stuffed a plain, brown envelope with the bill, a check and a wad of LIPA newspaper ads on which he had scrawled "Stop wasting our money!" And, as usual, he completed the package by printing "LIPA sucks" on the front of the bulky envelope. Everything was normal until Tuesday night, when a Nassau County police detective called Kohn at his Central Islip home and asked him to appear at the Eighth Precinct station house the...