for adanved ansi/irc art on all the channels download tdfiglet (alternative link), look at the source code and install it
in your irssi add an alias for tdfiglet:
/alias tdfiglet exec -out /home/epicmorphism/bin/tdfiglet -c m. save your config and go ahead test it out
irssi crapware theme: crapware.theme -- a cozy neon-ish theme. screenshot.
there are some other good themes like weed and neongold