- notify-send hello # works, but disappears too fast, and can easily be missed
- growl # advanced, haven't figured out how to use it
- knotify # apt-get install kde-baseapps-bin
- zenity # zenity --warning --text "meeting is now"
Hook one of these into your calendar application.
Or for IRC, using pidgin, try one of:
Or write your own pidgin plugin like I did, to use a notification system of your choice: