"By Grabthar's Hammer, by the Sons Of Warvan , you shall be avenged!"
Grabthar's Hammer was an object of nearly sacred importance to Dr. Lazarus. It was used as part of the oath, "By Grabthar's Hammer, by the Sons of Warvan, you shall be avenged."
It was first used in the film Galaxy Quest .
As with the Sons Of Warvan, Grabthar's Hammer is noteworthy for being fictional within an already-fictional universe. As such, it has no direct analog in American English.