1. In Accidents Will Happen, I find it hilarious when Squidward yells in SB's stethoscope "GET AWAY FROM ME!" and it keeps playing repeatedly in SB's stethoscope until SB puts his hands on his head. Very clever joke imo.
2. In Jellyfish Jam, I love it when SB literally moves without his hands or legs moving. The rock-moving sound effect also really helps the joke land.
3. I find the ending of Picture Day (underrated episode, mind you) to be hilarious (in a weird way.) Everyone else being human is kinda funny, and definitely an unexpected ending.