This just came to me so be cool. Take a giant flash game repository, something like all of Mochi Media or every single Kongregate game, add all of them to a single game container. It could be AJAX or Flash, whatever will make game load fast enough.
Add a chat room, a next game spin button and share game with a room button.
Key items will be a cool display while the randomizer runs (this will hide the game loading and some payoff for finding a new game or popular game
Optional items, avatars, graphical representation of the room.
Ok? Punch holes? Why would this not be a fun way to consume flash games and discover new ones?