Finally found a way to activate windows 8. this is 100% working, tested it personally. guys enjoy using windows 8. I also activates my windows 8 by this activator..
After extracting the downloaded rar file, run "Microsoft Windows 8 Activator(All Edition).exe" and let it load completly.
then click on "Windows 8 Install/Uninstall" and then CMD window will be open and just press "Y"
chill and relax.

there is another software in the package too , that one can be used for customizing the new start menu.

Note : IF YOU HAVE UPDATED YOUR WINDOWS AFTER THE ACTIVATION, YOU'LL NOTICE THE ACTIVATION IS GONE ! JUST OPEN THE SOFTWARE AGAIN AND ACTIVATE ONCE AGAIN.