Recently, my Mac Pro has been locking up while in the middle of a game... the game just stops responding... if I push the power button, I can hear drive activity as if it's trying to go to sleep but nothing happens... my EyeTV recording also stopped at the same time as it locked up... if I do cmd-opt-esc, I can hear drive activity but nothing happens...

Sound familiar to anyone?

yep, sounds familiar.

I got it only a few times, i just reboot and used the last Auto-save to continue.

If you are playing in full screen mode the UI probably can't display the Force Quit dialog over the game screen. I would suggest running in Windowed mode if you want to be able to force quit a hung game without having to reboot the whole Mac.

Recently, my Mac Pro has been locking up while in the middle of a game... the game just stops responding... if I push the power button, I can hear drive activity as if it's trying to go to sleep but nothing happens... my EyeTV recording also stopped at the same time as it locked up... if I do cmd-opt-esc, I can hear drive activity but nothing happens...

Sound familiar to anyone?

It is possible you are experiencing a kernel panic (which is suggested by the fact that other programs lock up too). This is basically the nastiest crash you can get as you have to reboot. Sometimes you will get a nice dialogue telling you that the computer has locked up - but most times you don't. This has happened to me a number times on my MacBook Pro. If you check your logs there might be a panic log which you could send to Aspyr for them to try to fix the problem (if you are lucky).