Here's a cool site that I've been playing on for about a year now, and they've just launched with a few new shows:
It's all full-video interactive, TV2 style Game Shows. Note that they are all British, so the game play may be a bit different, and the hosts surely are. And the trivia-based games are much harder!
Here's the shows they've got up now:
Who Wants to be A Millionaire?
Deal or No Deal
Family Fortunes (Family Feud)
Countdown (A personal favorite!)
If you live in the US, only the "View for Free" option is available. This means that while you can't win any money, you can still play along, and there's a couple of Ad Breaks.
Very cool use of the flash technology.