Crontab UI - Easy and safe way to manage your crontab file
Free Alarm Clock - Free Alarm Clock is a free, full-featured and user-friendly computer alarm clock for Windows.
Scheduled tasks - GNOME GUI for configuring a users' cron (automatic jobs). Some of its features are:
Gnome Clocks - Clock application designed for GNOME 3
024h Lucky Reminder - 024h Lucky Reminder is a reminder software for home and office.
AlarmDJ - Online Alarm Clock - Use YouTube videos or MP3 files as alarm sound. Works offline.