play-glass

#!/usr/bin/perl
use strict;
use warnings;
use POSIX qw(setsid);

&daemonize;
exec("mplayer -really-quiet -noar /usr/share/sounds/gnome/default/alerts/glass.* &> /dev/null");

sub daemonize {
    chdir '/' or die "Can't chdir to /: $!";
    open STDIN, '/dev/null' or die "Can't read /dev/null: $!";
    open STDOUT, '/dev/null' or die "Can't read /dev/null: $!";
    defined(my $pid = fork) or die "Can't fork: $!";
    exit if $pid;
    setsid or die "Can't start a new session: $!";
    umask 0;
}

sounds.pl

use strict;
use Irssi;
use vars qw($VERSION %IRSSI);

$VERSION = '0.1';
%IRSSI = (
        authors     => 'Kenny Parnell',
        contact     => '[email protected]',
        name        => 'sounds',
        description => 'Play sounds for different events in irssi.',
        license     => 'GNU General Public License'
);

sub priv_msg {
        my ($server,$msg,$nick,$address,$target) = @_;
        `~/.irssi/play-glass`;
}

Irssi::signal_add("message private", "priv_msg");

For the mac inclined:

exec("mplayer -really-quiet -noar /System/Library/Sounds/Purr.aiff &> /dev/null");