I think with any computer (I use Linux), if you tab your browser and keep one particlular game up, there is a low popping sound that alerts you when it's your turn. Also--I used to use an add-on for the Firefox browser that you can use to tell you when it's your turn in all your games (I believe I downloaded it right here).
Hope this helps!
Actually, I just found it and installed it. Go to resources (at the top) and then "Downloads". There will be a search box - type "Firefox" and it should show you a link to the download. Use the link (not the direct download), it will be easier.
Of course, this all depends on whether you are running Firefox on the Mac...
I'm using Chrome actually 
, thanks though.
The other thing is that this is contingent on the browser being open. Was kinda hoping for a dock / tray notifier.
Any apps to notify when my turn comes, etc?