An oldie but goodie:
Date: Fri, 1 Apr 1994 00:03:07 -0500
Subject: A.Word.A.Day--incunabulum
in.cu.nab.u.lum \.in-ky*-'nab-y*-l*m, .in_e-\ n, pl -la \-l*\ : a
book printed before 1501 (and therefore, literally "from
the cradle" of art of printing books)