10 Star Trek Moments You Never Knew Were Improvised
1. Vulcan Salute - Amok Time
The physical Vulcan salute was devised by Leonard Nimoy during the making of the episode, Amok Time. He was originally scripted to walk up to T'Pau and greet her normally, without any ornamentation. However, he cited the fact that so many different cultures have their own gestures when greeting someone that he felt he could introduce something here.
The sign made by the hand stems from Nimoy's Jewish childhood. It forms the letter 'shin', which represents the honorific title 'Shaddai', translating to 'Almighty God'. It is generally performed on both hands by Kohanim, who are Jews of priestly descent, on holy days. The ceremony that features this is generally not to be viewed, with the congregation asked to close their eyes. Nimoy remembered sneaking a look and seeing it, with it staying in his memory forevermore.
He then suggested using this to director Joseph Pevney. This presented a small issue, as actress Celia Lovsky who played T'Pau was unable to perform the gesture. This was fixed by simply having her use her other hand to position her fingers while off-camera. Nimoy credited writer Theodore Sturgeon as coming up with the lines 'Live Long and Prosper.'