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

Cassandra: Do those expensive shoes come with a name?
Lex: Lex Luthor.
Cassandra: Huh. Of Luthor... Everything Incorporated?
Lex: More or less.

Clark: She saw it.
Nurse: Saw what?
Clark: Her future.