Peace and long life, live long and prosper. - Mr. Spock.
A hand gesture consisting of a raised hand, palm forward with the fingers parted between the middle and ring finger, and the thumb extended, like this: 🖖. The gesture, primarily seen in the Star Trek series (usually used by Vulcan science officer Spock), was based on a priestly blessing used by Jewish Kohanim.
In the context of Danbooru, this is a variation of the v gesture.