Susan Basso -- Texas

Basso lured an older, retarded man (Louis "Buddy" Musso, 59, mental age 8)
to Texas with the promise to marry him.  Instead, she got him to make her
his sole heir, then murdered him for his life insurance.

Because the life insurance stipulated that it would pay more if the victim
died a violent death, Basso and her accomplices made his death as violent
as possible. 

While forced to kneel on a small mat, Musso was beaten with bats, belts, hands, 
kicked with combat boots and burned with cigarettes. His body was covered in 
bruises and cuts from head to toe and had several broken bones. Between beatings, 
he was forcibly scrubbed with a wire brush and bathed in a skin-peeling mix 
of household cleaners.  His skull was fractured, several bones were broken, 
and his skin was covered with cigarette burns.

http://www.awol-texas.org/articles/tragicarticles.html

http://venus.soci.niu.edu/~archives/ABOLISH/rick-halperin/oct99/0216.html

http://venus.soci.niu.edu/~archives/ABOLISH/rick-halperin/mar99/0472.html