Bot simples usando socket no Python:

import sys
import socket
import string

HOST="irc.freenode.net"
PORT=6667
NICK="pyAvelino"
IDENT="pyAvelino"
REALNAME="pyBotIRC"
readbuffer=""
CHANNELINIT="#channel"

s=socket.socket( )
s.connect((HOST, PORT))
s.send("NICK %s\r\n" % NICK)
s.send("USER %s %s bla :%s\r\n" % (IDENT, HOST, REALNAME))
s.send('JOIN %s\r\n' % CHANNELINIT)

while 1:
# readbuffer=readbuffer+s.recv(1024)
readbuffer=s.recv(1024)
print readbuffer
temp=string.split(readbuffer, "\n")
readbuffer=temp.pop( )

for line in temp:
    line=string.rstrip(line)
    line=string.split(line)

    if(line[0]=="PING"):
        s.send("PONG %s\r\n" % line[1])