DOSC TWiki snapshot as of mid-2005
quoting from the JargonFile,
"*Luser Attitude Readjustment Tool*. 1. n. In the collective mythos of scary devil monastery, this is an essential item in the toolkit of every BOFH. The LART classic is a 2x4 or other large billet of wood usable as a club, to be applied upside the head of spammers and other people who cause sysadmins more grief than just naturally goes with the job. "