Instant Messaging & VoIP

Free

SocialBox is a nice Instant Messaging app for Facebook.

Free

With Livescribe Connect for smartpen, you can send notes and audio as pencast.

Free

Make voice and video calls and send messages from your Mac.

Free

iGlasses helps you enhance the appearance of your video chats.

Free

Chat application that tries to integrate most of the major chat networks into one application.

Free

X-Chat Aqua is a freeware Mac OS X IRC client created by Steve Green.

Free

Discreetly connects to Calendar and notifies you of Zoom meeting details in real time.

Free

Supports private and group communication as well as file exchanges.

Free

Combine different means of communication.

Free

Traditionally, chat clients on the Mac have been anything but glamorous.

Free

iGlasses allows you to adjust and manipulate your webcam's video settings.

Free

Spark is an open source, cross-platform instant messaging client for businesses.

Free

aMSN is a powerful and efficient instant messaging client.

Free

Stay in touch with your colleagues and monitor conversations.

Free

Integrated functionality for instant messaging,presence, conferencing and voice.

Free

VoIP program which allows you to make phone calls over the internet.

Free

QQ connects you to over 600 million Chinese QQ members and many of your favorite websites and useful tools.

Free

Make HD video and voice calls and chat with friends.

Free

Communicate with your friends and colleagues using your Mac keyboard.

Free

Send messages, exchange files, and make voice and video calls.