In '30 Rock,' the Sheinhardt Wig Company Patch is a recurring joke and a nod to the fictional conglomerate, Sheinhardt Universal Electric Corporation. The patch appears on various uniforms and clothing items worn by characters throughout the series. It's one of the many humorous elements woven into the show's intricate storyline, serving as a quirky detail that adds to the absurdity of the '30 Rock' universe.