Feem - Share files offline. No servers. No cloud. No limits.
Freshservice - Freshservice: the one-stop cloud solution for all your IT management needs.
Winpopup LAN Messenger - Winpopup LAN Messenger is a cost-effective Office, Corporate, Enterprise Instant Messaging solution.
Freshdesk - Freshdesk is a cloud-based customer support software that lets you support customers through traditional channels like phone and email, social channels like Facebook and Twitter, and your own branded community
qchat - QChat is a simple crossplatform LAN chat.
Zendesk - Zendesk is a beautiful, lightweight help-desk solution.