Thema's DescBot plugin.
The idea of this plugin is to add a certain amount of bot support or the PJirc applet.
When sending text to the source, via the input, popup menus, setTextfield(), or sendString() methods
This plugin will interpret any key that is supplied via the parameter

<param name="descbot:textresponder<x>" value="somekey My response">

You can prefix all the keys using the parameter

<param name='descbot:respondercmd' value='!'>

This will help to better define the triggers, and separate multiple bots that
may use the same trigger values.
The default is '!'

In addition to the definable triggers the applet will respond to calls to
it's current nick in the form of:
!Nick
!Nick_help

Calling !Nick will, if the parameter 'descbot:nickresponder' is set to true, 
make the bot reply with it's description as set in the 'descbot:nickresponse' parameter.
This value can be changed at runtime with the alias
/desc My New bot description.

Other runtime commands are:
/addkey key description
/delkey key

Calling !Nick_Help will make the bot send a list of command keys that it has been
configured to respond to.

The plugin will also exchange any instance of these variables $me, $nick, $chan.
$me for the bot's current nick (all)
$chan for the current channel (only in a channel source window, or in bot replies)
$schan for the channel name without the # in front. Very useful for /url commands.
$nick for the current nick (only in PMs and popups, or in bot replies)

An example config is:
<applet name="applet" code=IRCApplet.class archive="irc.jar,pixx.jar,descbot.jar" width=640 height=400>
<param name='CABINETS' value='irc.cab,securedirc.cab,pixx.cab,descbot.cab'>

<param name="plugin1" value="adnd.DescBot">


<param name='descbot:respondercmd' value='!'>
<param name='descbot:scriptvariables' value='true'>
<param name='descbot:nickresponder' value='true'>
<param name='descbot:nickresponse' value='Hey $nick you are in $chan with me and my name is $me'>
<param name='descbot:textresponders' value='true'>
<param name='descbot:textresponder1' value='Hi $nick did you want to say Hi to $me in $chan?'>
<param name='descbot:textresponder2' value='Meeps $nick Meeps is a word I use to indicate that I am lost'>
<param name='descbot:textresponder3' value='Hell $nick Hell is being with $me in $chan'>

Of course you will need the usual minimum applet parameters on top of this to make it work.

Added:
If you now use $me in the key you can personalise the command to your bot. IE:

$me_Hug $me gives $nick a big hug!

This will make the bot respond to <MyCurrentNick>_Hug thus making it able to differentiate between this PJirc instance,
and a possible roomfull of similarly configured applets.