Here are some games from the web you can play:

Plastic Surgery Lab: The cast of Friends (mrshowbiz)
The (New and Improved) Friends Drinking Game (friends-cafe)
Friends Trivia #1 (NBC)
Friends Trivia #2 (NBC)
Magic 8-Ball (deletetheinternet)
The Ultimate Scream Test (E! Online)
Couples Concentration (E! Online)
Celeb Driving School (E! Online)
Jigsaw puzzle (cast playing poker) (JigZone)
Jigsaw puzzle (cast with The Rembrandts) (JigZone)
Jigsaw puzzle (cast walking on street) (JigZone)

Here are games I made myself (some use java or javascript):

TicRossRachel - a cute TicTacToe game
Ross and Rachel concentration game
Ross and Rachel puzzle
Find the differences
Crossword (names of episodes)


The followings games you have to download to your computer:

Friends Fortune - a Friends "Wheel of Furtune" game
Friends Trivia Game