that would be nice since I believe that the solution mentioned above won't help windows users. Unfortunately I lack the skills to implement this, but maybe someone else might ;)
Windows users can get ports of GNU utilities with projects such as unxutils.sf.net, tac is listed.
Or go the whole hog and use cygwin (full shell/cron/etc support).
-- Andrew Janke (a.janke@gmail.com || http://a.janke.googlepages.com/) Canberra->Australia +61 (402) 700 883