Murr's Blanket is Murr's most treasured possession. It was knitted by his late grandmother when he was a kid. He still sleeps with it at night. It has been used against him in punishments at various points in the show.
The blanket first appeared in Charity Case. It was shown in a photo of Murray before he shaved his chest hair, lying on his bed underneath it. It was then used in Murr's art punishment in Art Attack and was put on a sculpture of Murr.
In Doomed, Murr is the episode's biggest loser. The blanket makes it's first live appearance (supposedly). Murr was strapped into some stocks and forced to watch as a strange man speaking in tongue supposedly threw it into a bonfire. Murr was furious over his blanket being ruined until Joe reveals that it was a decoy. Just as Murr sighs in relief, however, Joe throws the blanket in the fire anyway, making Murr angry again. However, Murr later revealed on Twitter that the actual blanket was safe and sound in his apartment and that Joe used another decoy to trick him.