“Sometimes it’s useful to give a reminder to yourself — like to
tell you when it’s time to get off the computer. Here’s a few
simple and effective ways to use Linux and open source tools to
make reminders for either later in your current login session, or
for the next time you log in.”
“Sending yourself a short email message is often effective for
reminding yourself to do something during your next workday or the
next time you read email; keeping a message in your INBOX works as
a constant reminder to get something done — provided you don’t
abuse it and fill your INBOX with lots of these “urgent”
mails!”
“Use the leave tool to remind you when you have to leave (you
can get either the Debian package or its original NetBSD sources…
at debian.org). Give as an argument the time, in 24-hour format,
when you have to go.”
“The sleep tool does nothing but wait (or “sleep”) for the
number of seconds specified as an argument. Use this followed by a
; character (the shell command separator) and another command to
run that command after the amount of time you specify. This is
useful to run a command at a later time during your current
session.”