On FreeNode, I auto join these channels when I bother to start my IRC client, which may or may not happen any given day.

#trilug (Triangle Linux User's Group)

#trijug (Triangle Java User's Group)

#trilug-mtb (people in trilug who ride MTBs)

#fedora

#centos

#asterisk

#centos

#openmoko

#java

#eclipse

#spring

#jboss

#hibernate

#ruby

#erlang

#prolog

#lisp

#ai

#swig

#machinelearning

#openqabal