What are some alternatives?
When comparing IP Messenger and Simple Chat, you can also consider the following products
LAN Messenger - LAN Messenger is a decentralized UDP IM-style chat client which supports usernames...
BeeBEEP - You can message and share files inside your intranet without a server.
Ruler - It's a screen ruler for Windows.
KouChat - KouChat is a simple serverless chat client for local area networks (wifi).
Feem - Share files offline. No servers. No cloud. No limits.
BORGChat - BORGChat is a LAN messaging software program.