Feem - Share files offline. No servers. No cloud. No limits.
Dingtone - Dingtone is a free call and texting application for making unlimited calls and text messages to any number at the moment registered in any part of the world by any cellular company.
Winpopup LAN Messenger - Winpopup LAN Messenger is a cost-effective Office, Corporate, Enterprise Instant Messaging solution.
Textnow.com - It lets you text your friends, aka my only source of happiness
qchat - QChat is a simple crossplatform LAN chat.
FluffyChat - Open. Nonprofit. Cute ?