Let's see.
Glider Pro runs for a while but then freezes up mysteriously. From what I can see the mouse pointer is not visible so it's difficult to force quit the app.
Crystal Caliburn doesn't run at all, but then it didn't run on Mac OS 9 either.
Crystal Quest runs but strangely enough only in Black and White mode (no matter the color settings).
Diamonds appears to run fine.
The Activision Adventure Pack (I think that's what it's called) runs fine for joystick games like Pitfall and Frostbite, but the paddle controlled games like Kaboom seem overly sensitive (this may be an issue in OS 9, I'm not sure).
Many people say that Bugdom runs, but I don't find this to be the case. If you have the OEM version, it gives you a message that the game isn't licensed for your machine. If you get the latest "update" from their website I'm able to see the opening screen and hear music, but not able to see anything when the actual game play starts.
Still to test:
Star Trek 25 Anniversary
The Lost Legends of Infocom
Marathon
Pathways into Darkness
Spectre
World Builder
Reach for the Stars
and many more.
Yeah, I know the original poster was talking about modern games with cool graphics and sounds, but other than Budgom, these are the cool games that I've been playing on my Mac for years and it's incredibly unlikely that anyone will ever release an update or revision. That's just the sort of code that the Classic environment was designed to be used for.