Keppe Messenger

A Secure User Messaging System

Joomla Chat Extension

It can add a live chat room to Joomla and with multiple skins and single sign-in.

JomSocial Chat Module

It can add a live chat room to JomSocial, sixteen skins and users single sign-on.

Jitsi

Free messenger client supporting audio and video chats

JBuddy Messenger

InterFace Chat Messenger

Serverless Instant Messenger with open source Social Network, Chess Game and Forum and Groupchat function

Instant Messenger Spellchecker

A trial version app for Windows, by Interactivegt

Instant Messenger 2 (IM2)

Multi-network client compatible with MSN, ICQ, AIM, Yahoo Messenger and IRC

Indiana Jones 4 Messenger Skin

Feel like you’re part of the new Indiana Jones' adventure

IMterrupt

Block Instant Messenging, Web Chat, Web Games