screen, mouse, kb lockup

While attempting to stop a video playing on Macro Media Flash Player 7, I managed to lock out everything. I could not move the mouse cursor, the arrow keys and the rest of the kb didn't work, ctl-alt-del did nothing. None of the function keys did anything. (The video was something downloaded from the 'net via Firefox.) I wound up pulling the big switch, as us hams like to say. Is there anything else I could have done? I'm trying to put Linux to practical use, and this is the first time I've seen 10.0 crash, so it's good, but not fool-proof. (If something can be broken, this fool will break it!)