TowerTalk is a communication tool for intranets. It combines the powerful features of popular Instant Messengers, such as ICQ, AIM and Yahoo Messenger with the advantages of not having to rely on servers or a permanent connection to the internet. It allows you to talk to other users in your network, and lets you send messages to many hosts simultaneously. It also allows you to block messages which are not of interest for you, based on words or phrases, sending users or other characteristics.
Currently, TowerTalk is not of much use for end-users, as it is in an early stage.
TowerTalk development has stopped. The reason why TowerTalk development has started has vanished. If you need a good OSS instant messenger, you might want to try Jabber. If, for whatever reason, you want to continue TowerTalk development, feel free to contact the project admin (Project page).