This program simply scans a text file for lines containing likely-looking dates.
It prints any lines containing today's or tomorrow's date (where Monday is considered “tomorrow” relative to Friday).
there is no provision for repeating reminders, so
you can't (for example) remind yourself of something on the first of every month.
cron
lets you specify dates in a relatively sophisticated format, so you can remind yourself of daily, weekly or monthly events.
Still, cron won't handle fairly simple things like events which happen on the first Wednesday of every month.
/usr/bin/gmessage -display :0.0 -center -geometry 800x400 -borderless -bg \"#000000\" -fg \"#00ff00\" -font \"40\" $str
For X Window desktops, the standard application would be xmessage. GNOME or KDE users may prefer gxmessage or kmessage, respectively.
osd_cat
will put the reminder on your screen no matter where you are as a "on screen display", not a window.
It comes up much like the volume bar on your TV does.
That way it can't be hidden.