Free Alarm Clock - Free Alarm Clock is a free, full-featured and user-friendly computer alarm clock for Windows.
Memo to Me - Online email & SMS reminder service.
Digital Clock 4 - Beautiful customizable clock with plugins
Simply Remind Me - Free email and text reminder service so you don't forget the important things in life!
Gnome Clocks - Clock application designed for GNOME 3
Desktop-Reminder - Desktop-Reminder is a freeware task planner for Windows to manage your tasks and other to-dos’ in really easy way.