skunkworks
A loosely organized research and development team or facility.
Not all ideas coming out of the Phillips skunkworks have been success stories, of course. A polyethelene saddle never even made it through the patent process.
Where it comes from
From skunk + works, since c. 1943. Skunk Works was the nickname of Lockheed Advanced Development Projects, eventually gaining official recognition. The name is derived from a mysterious, foul-smelling “skonk oil”-brewing facility called the Skonk Works in the comic strip L'il Abner by Al Capp.
Adapted from the Wiktionary entry skunkworks (CC BY-SA 4.0).