Rachel sang "Copacabana" at Barry and Mindy's wedding and they used "Looks Like We Made It" as a montage with Ross and Marcel in the episode where Marcel was in the movie (The One After The Superbowl, I believe).
Joey got an audition for a musical version of "A Tale of Two Cities"; what songs did he decide to sing for this audition?
"New York, New York" and "I Left My Heart in San Francisco"
My question (and it doesn't have a correct answer to my knowledge.) Who got who (or whom) for the Secret Santa Project Thanksgiving Season 4? Phoebe got Rachel initially. Joey didn't get Chandler (he requests for him at the end of the episode). Ross got Monica but wants to switch because he's already getting her something for Hanukah. Chandler firsts try to trade for Rachel and then is after Ross. I think we can assume that nobody got themselves.