I am going to provide you guys with useful links, tools that I have found useful in both normal day to day use of computer and some advanced tools for techies. I hope you find these useful.
PS: I will not suggest a program that has spyware. Some may have small innocent ads.
I start with FireFox Prayer Time Plugin
And for those who do not use FireFox, people have developed Prayer Time Sidebars for Vista or you can download the Athan software if you don't have Vista or do not like sidebars.