KAlarm

KAlarm is a personal alarm message, command and email scheduler.

You can set up alarm messages which pop up on the screen at the chosen time (with sound if desired), or you can schedule commands to be executed or emails to be sent.

When configuring an alarm, you can:

For alarm messages, choose whether to type in your own text message, display the text generated by a command, or display a text or image file.
Configure the alarm to recur on an hours/minutes, daily, weekly, monthly or annual basis, or set it to trigger every time you log in. You can also specify a repetition within a repetition. Alarms can be constrained to occur only within working hours.
Specify that a reminder should be displayed in advance of the main alarm time(s).
Choose a color and font for displaying the alarm message.
Specify an audible beep or a sound file to play when the message is displayed, or specify that the message is to be spoken.
Choose whether or not the alarm should be cancelled if it can't be triggered at its scheduled time. An alarm can only be triggered while you are logged in and running a graphical environment. If you choose not to cancel the alarm if it can't be triggered at the correct time, it will be triggered when you eventually log in.
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It is possible to use multiple alarm calendars, which for example enables you to share alarms between a laptop and desktop computer.

Alarms may also be scheduled from the command line, or via D-Bus/DCOP calls from other programs.