Paint twirler
Place a ghost brick, hit E to take out your paint can, and hold the primary fire button (Left mouse button) and hit Number pad 7, 8 ,9 1, 2, or 3 to shake the paint can around while using it, make sure your ghost brick is still active though
Invisible drum sticks
Place a ghost brick, and un-equip the Brick item, then type /hug into the chat, then hit Number pad 3 for the right hand to move down and Number pad 1 to move both hands down
You can do this to make it look like you're drumming a drum beat: Number pad 3, Number pad 3, Number pad 3, Number pad 1, and repeat