[Arkady]

Yvonne Craig was the luscious actress who played both Batgirl and the green alien who danced for Kirk.

[wny]

she even looked good green!

[Dr. Franklin]

Here's an interview Yvonne Craig did about her Star Trek guest appearance. She regrets not stealing the costume, which she says was made by someone who designed costumes for Les Folies Bergères, a Paris girlie show:
Yvonne Craig discusses her Guest Shot on Star Trek as Marta