Windows Vista has a nice feature of showing the amount of free space available on a disk graphically showing the drive’s free space with a smooth colored horizontal bar below the drive icon, the same can be achieved  in Windows XP as well using Vista Drive Icon.

This is how your drives look after installation

Vista Drive Icon also works with All 32-bit MS Windows (95/98/NT/2000/XP).

Download Vista Drive Icon.

Via – Shivaranjan.com