The Jargon File (version 4.4.7, 29 Dec 2003):

baggy pantsing
 v.

    [Georgia Tech] A ?baggy pantsing? is used to reprimand hackers who
    incautiously leave their terminals unlocked. The affected user will come
    back to find a post from them on internal newsgroups discussing exactly how
    baggy their pants are, an accepted stand-in for ?unattentive user who left
    their work unprotected in the clusters?. A properly-done baggy pantsing is
    highly mocking and humorous. It is considered bad form to post a baggy
    pantsing to off-campus newsgroups or the more technical, serious groups. A
    particularly nice baggy pantsing may be ?claimed? by immediately quoting
    the message in full, followed by your sig block; this has the added
    benefit of keeping the embarassed victim from being able to delete the
    post. Interesting baggy-pantsings have been done involving adding commands
    to login scripts to repost the message every time the unlucky user logs in;
    Unix boxes on the residential network, when cracked, oftentimes have their
    homepages replaced (after being politely backed-up to another file) with a
    baggy-pants message; .plan files are also occasionally targeted. Usage: ?
    Prof. Greenlee fell asleep in the Solaris cluster again; we baggy-pantsed
    him to git.cc.class.2430.flame.? Compare derf.