Free Alarm Clock - Free Alarm Clock is a free, full-featured and user-friendly computer alarm clock for Windows.
Reminder Commander - Reminder manager that reminds you about important events in advance.
Gnome Clocks - Clock application designed for GNOME 3
JIT Scheduler - JIT Scheduler is a task scheduler for Windows 95/98/ME/NT4/2000/XP/2003.
AlarmDJ - Online Alarm Clock - Use YouTube videos or MP3 files as alarm sound. Works offline.
Memo to Me - Online email & SMS reminder service.