Yesterday, the two were in Harlem shooting a commercial for 50 Cent's latest venture, his Street King energy drink.
The premise of the video is that poor 78-year-old Joan Rivers needs a pick-me-up while working out at the gym.
It seems like a fun time was had by all. During shoot, the two were really chummy with each other on Twitter:
Awww, how cute. The two make a great power couple!
Access Hollywood was on set while they were shooting the commercial and they shot this nifty video where 50 and Joan both talk about working with each other.