The dev lead for my group stopped by my office just now to chat for a bit, and somehow we wound up in a "who posted to USENET first?" contest. This of course led me to search for my oldest post - and it turns out it was quite a while ago - I apparently posted to rec.music.industrial on Sunday, May 24, 1992, although I don't really have any recollection of ever having done so.
This means I beat André - his was on Tuesday, October 13, 1992, in sci.energy. Score!
When was your first USENET post?
PS: Dear LiveJournal, please stop freaking me out with your $0.99 tchotchkes. Thank you.