As the name implies, TapDex gives you a one-tap access to your Mac OS X Address Book.
Tap the customizable hot key and up pops a search window. Start typing and the set of matching entries narrows down in real-time.
When you find the entry you're looking for, you can email the contact or map her address all without leaving TapDex or launching Address Book.
TapDex is small, fast and takes up little precious resources. It is designed to run in the background and activated with a hot key. Customize it to auto-launch on log in and all your Address Book contacts will always be one tap away!