My all-time favourite Joey/Phoebe moment was from TOW The Cheesecakes -- when Phoebe had to say goodbye to David, she thought Joey was coming up to chastise her for breaking their dinner date.
Instead, Joey said was more than understanding and gave Phoebe a big hug. When Joey asked Phoebe what he could do to make her feel better, she said that David could come back from Minsk if Joey "could achieve positron distillation of subatomic particles."
Joey said he could give it a shot ... so, take that, Days of Our Lives!
Love Joey -- he is such a true friend to all his friends.