My evil twin is Frances.

Proof of evilness:
-Works for IBM
-Is British
-Has white pupils
-Uses black and white photography to disguise evil lair
-Resembles me
-Shares my name

...Or perhaps she's the good one. Oh dear.

Frances - please don't take offense. Obviously if you're my twin I must hold nothing for you in my heart but sisterly love.

And what kind of parent gives her twins the same name? Talk about inconsiderate.