It’s side-splitting. — Это уморительно. (Jokes of this stand-up comedian are side-splitting.)

It tickles my funny bone. — Это меня так веселит. (She’s amusing and knows how to tickle my funny bone.)

It’s priceless. — Это очень забавно. (Your facial expression is priceless.)

Joke is a hoot. — Шутка на разрыв. (Remember Josh? Yesterday he told me a joke that was such a hoot.)