KAlarm lets you schedule personal messages to display, audio files to play, commands to execute, or emails to send. Among its options, it allows you to choose the message font and color, recurrence schedule, whether to display an advance reminder, whether to speak the message or play a sound when it is displayed, and whether to cancel the alarm if it can't be triggered on time (e.g. if you are logged out at the time). As well as using the graphical interface to configure alarms, you can use the command line, and there is a D-Bus/DCOP interface for other applications.
