Season 6, Episode 5 - The Holographic Excitation
In this Halloween episode, Boba Fett and Slave I appear on a poster in the comic book shop.
Season 3, Episode 9 - The Ornithophobia Diffusion
00:11:12 - 00:11:30
Sheldon attempts to scare off a bluejay from his apartment balcony by coming out of a closet with a Boba Fett helmet, which fails to frighten the bird.