These are hilarious:

With a Little Help From My Friends

Octopus’ Garden

I’m Looking Through You

She Loves You

Blackbird

Ob-la-di-ob-la-da

Good Day Sunshine

While My Guitar Gently Weeps

Act Naturally

Letter B (Let it Be)

Source: The Best Muppet Show Beatles Covers

Top Hat Sasquatch

Hat tip GMSV