Published at LXer:

Finally, an answer you can give your kids when they get up the nerve to ask :) We made it to another weekend (somehow) by working, and/or sleeping and/or both for another 5 days ;) It's time for a joke or two to help us forget the fact that we're on-call all weekend :P

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They're the "funny-manpages", Debian users can install easily them through apt, other systems have them as well, though it might be more work. Here's a list of others included in the package:

/usr/share/man/man1/date.1fun.gz
/usr/share/man/man1/echo.1fun.gz
/usr/share/man/man1/gong.1fun.gz
/usr/share/man/man1/grope.1fun.gz
/usr/share/man/man1/party.1fun.gz
/usr/share/man/man1/rescrog.1fun.gz
/usr/share/man/man1/rtfm.1fun.gz
/usr/share/man/man1/rm.1fun.gz
/usr/share/man/man1/tm.1fun.gz
/usr/share/man/man1/xkill.1fun.gz
/usr/share/man/man1/baby.1fun.gz
/usr/share/man/man1/celibacy.1fun.gz
/usr/share/man/man1/flog.1fun.gz
/usr/share/man/man1/uubp.1fun.gz
/usr/share/man/man1/condom.1fun.gz
/usr/share/man/man1/flame.1fun.gz
/usr/share/man/man1/xlart.1fun.gz
/usr/share/man/man6/sex.6fun.gz
/usr/share/man/man3/strfry.3fun.gz
/usr/share/man/man1/egrope.1fun.gz
/usr/share/man/man1/fgrope.1fun.gz