haha , frnds when we miss our xp key for formatting , we call to ur frnds to get it .
But it is just Right Under your Nose! To get the Windows XP CD key, you have to do the following steps. Just follow the following steps and find Windows XP cd key into your windows XP CD.

Steps to follow to find Windows XP CD key:
1. Bring your Windows XP CD and insert it into your computer’s CD/DVD ROM/ RAM.
2. Now, browse your Windows XP CD and find the folder I386.
3. Inside I386 folder, find the file named as unattended.txt.
4. Open unattended.txt by using notepad.
5. At last, keep scrolling of the opened file and you will get Windows XP CD key.

The people who are not wish to buy XP or the people who lost the serial key of Windows XP CD, can find the Windows XP CD key in this way.
( I hav worked out in windows xp sp-2 , you try in other versions too.. )