Painstiks, in use.
The Painstik is a Klingon ceremonial device, used to inflict pain. It is used in the Age of Ascension ceremony, where, in the final part, a young Klingon must walk between two lines of Klingons, suffering the painstiks, and reaching the other end, before he can call himself a warrior.
In 2365, Wesley, Data and Geordi re-created the Klingon 10th Anniversary ceremony of the Age of Ascension for Worf in a holodeck onboard the Enterprise-D. (TNG: "The Icarus Factor")
Painstiks are also used in the Sonchi ceremony to confirm the death of a Klingon chancellor. The chancellor's body is prodded with painstiks by the Arbiter of Succession and the contenders to become the new chancellor while issuing verbal challenges. (TNG: "Reunion")
The Ritual of Twenty Painstiks is a portion of the ceremony of the Day of Honor. (VOY: "Day of Honor")