I wrote this one to discipline my work hours and increase my productivity. It's a very very crude alarm clock that you control with the Scroll Lock key.
Press the scroll lock key once and it asks you when should the alarm bell ring. Enter desired time in the HHmm format (i.e. 1830 for 6:30 p.m.) and don't turn off the computer.
The program is very crude, and it does not check the validity of the time you entered. So don't set the alarm to 18301 or to minnesota. Nothing serious should happen. It just wouldn't ring.
To change the alarm time or disable the alarm, press scroll lock again and read the instructions (two short lines, really).
Anyway, the source code is in the archive. There is also the compiled exe. Place alarm.wav in the same folder with the exe, and just run the exe.
Let me know if you like it.