I run a stand-alone IRC (Internet Relay Chat) server.  It's a bit like
conversating over packet radio.  Using your favourite IRC client,
connect to irc.sm5sxl.net.  Join the #hamradio channel for general
radio chat.

Examples of good IRC clients are mIRC for Windows, Ircle for Macintosh
and XChat (graphical interface) or ircII (console) for Unix-like
operating systems.
.