Sharashka (sometimes Sharaga or Sharazhka, Russian: шара́жка, Russian pronunciation: [ʂɐˈraʂkə]) was an informal name for secret research and development laboratories in the Soviet Gulag labor camp system. Etymologically, the word sharashka is derived from a Russian slang expression sharashkina kontora ("Sharashka's office", possibly from the radical meaning "to beat about"), an ironic, derogatory term to denote a poorly organized, impromptu, or bluffing organization. Official name was ОКБ that is Опытное конструкторское бюро that can be translated as "Experimental Design Bureau".
The scientists and engineers at a sharashka were prisoners picked from various camps and prisons and assigned to work on scientific and technological problems for the state. Living conditions were usually much better than in an average taiga camp, especially bearing in mind the absence of hard labor.
The results of the research in sharashkas were usually published under the names of prominent Soviet scientists without credit given to the real authors, whose names frequently have been forgotten. Some of the brilliant scientists and engineers imprisoned in sharashkas were released during and after World War II, continuing independent careers and becoming world-famous, such as Léon Theremin.
In 1934 Leonid Ramzin and other engineers sentenced in the Industrial Party Trial were formed into a special design bureau under State Political Directorate (GPU), which was then the Soviet secret police.
In 1938, Lavrenty Beria, a senior NKVD official, created the Department of Special Design Bureaus at the NKVD USSR (Отдел особых конструкторских бюро НКВД СССР). In 1939, the unit was renamed the Special Technical Bureau at the NKVD USSR (Особое техническое бюро НКВД СССР) and placed under the leadership of General Valentin Kravchenko, under Beria's immediate supervision. In 1941 it received a secret name, the 4th Special Department of the NKVD USSR (4-й спецотдел НКВД СССР).
In 1949, the scope of sharaskas significantly increased. Previously the work done there was of military and defense character. The MVD Order № 001020 dated November 9, 1949 decreed installation of "Special technical and design bureaus" for a wide variety of "civilian" research and development, particularly in the "remote areas of the Union".
The 4th Special Department was disbanded in 1953 when, shortly after Stalin's death, Nikita Khrushchev had Beria arrested for espionage and executed.
Notable sharashka inmates 
- Aleksandr Solzhenitsyn, a writer. His novel The First Circle is a vivid account of life in sharashka Marfino.
- Lev Kopelev, a writer, another inmate of Marfino (a prototype for Rubin from The First Circle)
- Sergey Korolyov, an aircraft and rocket designer, later the chief designer for the Soviet space program.
- Valentin Glushko, a chief rocket engine designer. (His biography at MN)
- Andrei Tupolev, the chief designer of the aircraft families Tu and ANT.
- Vladimir Petlyakov, the chief designer of the aircraft families Pe and VI (The Petlyakov aircraft).
- Vladimir Myasishchev, an aircraft designer.
- Leonid Kerber, an aircraft designer.
- Robert Ludvigovich Bartini (or Roberto Oros di Bartini) an aircraft designer and scientist.
- Helmut Gröttrup, a German rocket scientist from the Peenemünde laboratory. (Its head Wernher von Braun was acquired by the US).
- Nikolai Nikolaevich Polikarpov, an aircraft designer (arrested for a brief period).
- Léon Theremin, a pioneer of electronic music, the inventor of the theremin and a passive eavesdropping device.
- Nikolay Timofeev-Ressovsky, a geneticist and radiobiologist (His biography at genetics.org).
- Leonid Ramzin, the inventor of the straight-flow boiler (The Industrial Party affair, His biography in Russian).
- Yuri Kondratyuk, a pioneer of astronautics and spaceflight, the inventor of gravitational slingshot.
Modern usage of the term 
- L.L.Kerber, Von Hardesty, Paul Mitchell, Stalin's Aviation Gulag: Memoir of Andrei Tupolev and the Purge Era (Smithsonian History of Aviation & Spaceflight S.), Smithsonian Institution Press, (hardcover, 1996, 396p.), ISBN 1-56098-640-9.
- Maj David R. Johnson, USAF. "Review of Stalin’s Aviation Gulag by Leonid Lvovich Kerber". Aerospace Power Journal. Retrieved 2007-06-23.
- The database of research and design establishments of the Soviet defence industry, 1927–67 by Keith Dexter, The U. of Warwick.