Free Alarm Clock - Free Alarm Clock is a free, full-featured and user-friendly computer alarm clock for Windows.
ClocX - ClocX - freeware analog clock for Windows desktop with many features like calendar, alarms, skins, antialiasing and transparency.
Gnome Clocks - Clock application designed for GNOME 3
T-Clock Redux - T-Clock Redux in an enhanced fork of Stoic Joker's T-Clock 2010 with ISO week number support...
AlarmDJ - Online Alarm Clock - Use YouTube videos or MP3 files as alarm sound. Works offline.
Alarm Clock Xtreme - Alarm Clock Xtreme: Alarm, Stopwatch, Timer (Free) is the most popular alarm clock app created and published by AVG Labs for both iOS and Android devices.