CookTimer - CookTimer is a simple cross-platform countdown timer that helps when cooking, making tea or eggs.
TIMEBOX - An advanced timer for professional meeting facilitators
Online Stopwatch and Timers - Sometimes everybody need to count time for some reason.
MetaClock.com - MetaClock is an Online Alarm Clock that can play YouTube videos and uploaded MP3s as an alarm tune. It supports Chromecast which means you can turn your TV or stereo system into an alarm clock. No installation is needed, it can also work offline.
Hourglass - Hourglass is the most advanced simple countdown timer for Windows.
KukuKlok - Kukuklok is a free alarm clock available online and offline.