This is the Mister Mxyzptlk doll from The Big Bang Theory episode #15, Season 6, 'The Spoiler Alert Segmentation'.
Sheldon packs up Leonard's belongings after an argument and Sheldon calls out the items while Amy makes a list.
A picture of Scott London, TBBT Property Master, is included - he is holding the doll while in his prop workshop at the back of Stage 25 on the Warner Bros. Studios lot.
