|The following is based on Fallout Tactics and some details might contradict canon.|
She is great at throwing and she knows a bit about traps. Like most BoS soldiers Rusty also has a basic knowledge of small arms. She's called Rusty because of her flaming red hair. She's got very big hands, for a woman, though. 
Rusty uses the same character portrait as the female Boomer.
Rusty appears only in Fallout Tactics.