~/.crontab: Remind me when I want to be offline.

This is an experiment, let's see how it plays out for this first week.

.crontab

@@ -1,3 +1,5 @@
10 * * * * offlineimap -u ttyui > /home/lu/.offlineimap.log
*  * * * * /home/lu/.bin/warn-if-low.sh
*  * * * * date --rfc-3339=seconds >> /home/lu/.pings
* 0-7,19-23 * * * DISPLAY=:0 zenity --error --text "get off the computer!"