Jon's Phone Tool for Mac

From JNSoftware:

Jon's Phone Tool (JPT) is a versatile phone dialer for Macintosh.

Apple provided you with a digital hub. With JPT you can finally add your phone to the party. And we're not just talking about your Bluetooth mobile (though that's a good start). Prefer to use your landline? OK. How about Vonage, CallVantage, Speakeasy.net VoIP, BroadVoice VoIP, Skype, IP phones from Cisco or Snom, softphones from the Gizmo Project, CounterPath, LoudHush, JackenIAX, MegaFon, or ohphoneX, advanced telephony solutions such as Phlink, PhoneValet, or Fritz!Box? No problem. Are you getting the picture? JPT is versatile!

You can enter a phone number manually or you can use the integrated search tools to find numbers in your Address Book, Marketcircle Daylite, Microsoft Entourage, Now Contact, or Palm Desktop databases. You can also search various websites and with the included contextual menu and services, you can even select a number just about anywhere and instantly dial it using JPT.

JPT also has extensive AppleScript support, Bonjour notifications, caller ID, a call log, a notepad, and call timers as well as a fun and unique interface.