Stella Nickell
Poisoned her husband with cyanide-laced Excedrin, then randomly placed
more poisoned excedrin on store shelves to make it look like the act
of a crazed killer. One other person died. Thought to be a "copycat
crime" inspired by the Chicago Tylenol murders.
http://nickell.tierranet.com/tales/bruce.htm
http://wolfstories2.tripod.com/id25.htm