QuickSilver

QuickSilver. So far, I'm thrilled. Like my business partner, QuickSilver has freed me from the tyranny of the Dock. Five keystrokes gets me anywhere on my system. I'm particularly enamored with the Terminal plugin : instantly open a Terminal window in any directory on my drive. That plus the Address Book/ Mail integration and I can send emails without ever seeing Mail.app. I'm hooked.

I suggest checking out the Flashlight interface, too. Less obtrusive.