In this clip from next week's Smallville, "Stiletto," We see Lois in her superhero costume where she calls herself Stiletto. In this scene, Clark calls her out on being Lois.
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Smallville Quotes

Lex: I don't like riddles, Doctor.
Dr. Hamilton: Then this object will make you profoundly unhappy.

I've seen some strange things in my life, but this definitely takes the cake...well, almost.

Jonathan