Alarm Clock is a simple alarm clock for gnome desktop, it is a good choice if you need an alarm clock,counter,and birthday reminder. At present, the latest version of Alarm Clock is 1.4.3
Install
Alarm Clock is available from the official Ubuntu repository, but it might be old. You can use following command in terminal to install it.
sudo apt-get install alarm-clock
To install the latest version, just download the appropriate deb
package from : http://alarm-clock.pl/downloads, and double click to install.
Once installed, open Alarm Clock from Applications -> Accessories menu. Make it auto-run at start-up in Edit -> Preferences window.
Screenshot from Alarm Clock’s Homepage