There's a cool power in the Expanded Psionics Handbook called time hop, which basically projects a target forward in time for a couple of rounds. To have a room where that randomly seems to happen to people and objects might be a cool environment.
Also, other creatures interacted with could have some kind of weird, visual stuttering effect, like when you're trying to watch a movie but the device you're playing it on is old or messed up and can't keep up with the data stream. Perhaps auditory effects could cut out for a brief moment (or a round or two), as time streams try to sync back together.
What if things seem to fall really slowly? Or time flows in different rates for different objects. The plants in the corner might germinate, bloom and wither before the players very eyes.
Time measurement devices no longer work. They just get stuck at one particular time. Spell durations are all extended. Instantaneous spells hiccup and go off a round after they are cast.
Certain events keep repeating themselves, disasterously, until the players finally get it right.
Just some thoughts. Cheers,
Vurt