Copied from the in-game forums, very interesting for bat client users:
From: Amarth
Posted: 18:40 09/03/2008
Level: 600 [Wizard]
Age: 8y, 15d, 16h, 29m, 15s
As you know, Batclient shows your target and it's condition in the small h
ealthbar window. Several people seem to peculiarly like this about the
client.
Besides this, I'm starting to think the more advanced targeting stuff has
slipped past several Batmudders, so I will post about it:
If you left-click on an occupied slot in the party frame you will "select"
that player and put the name of the player into a global variable called
"partyTarget".
To tell the person you have clicked on you can use:
"tell @partyTarget your message".
With this variable you can assign keys or macros to perform certain actions
against the selected party member. For example, you could set F1 to heal
selected member and when you see their health bar go down, you'd just click
on their slot and press F1. Of course, the target is remembered for repeated
healing until you click on someone else.
There are also two more global variables are available. "@selectedTarget",
which will be set whenever you click on stuff in the main text window for
example, and "@latestTarget" which will be set whenever you click somewhere
both in the party frame and in other windows.
Amarth Shadowstring