One of the things I built into my crowbar dictionary attack tools for DMG and keychain files from the start was Growl. Growl is a free add on notification framework for your mac. MANY popular mac programs support growl so this is not just some odd plug in. I recommend in the crowbar apps making it popup the notifications for password found and not found at least go to your screen. The password found is even better when set to sticky. This means the alert stays on the screen until you click on it.
Now if you have an iPhone you can get the alert notifications right to your iPhone. There is a great iPhone application called Prowl (App Store Link). The developer’s site lets you create a login to his site which you set in the Prowl program. You download and install a Growl plugin for Prowl. The Prowl iPhone app is $2.99. The service and plugin are free. Last all you do is customize the alert settings for the crowbar apps to send to Prowl just using the growl preference pane control.
Now when you leave those real large dictionaries running you can leave them minimized and even leave the office or home knowing you will get the status when the job finishes.
You can find out everything at the Prowl developer’s site: http://prowl.weks.net/