I have a multi-card reader to my desktop running Vista Premium. Now
in My Computer I have 4 drive letters, and each is labeled as "Removable
Drive". I've changed the drive names and icons by doing this

Navigate to:
HK_LOCAL MACHINE\SOFTWARE\Microsoft\Windows\Current Version\explorer
and added a new Key called "DriveIcons" I can add new Keys under that for
each Drive to specify the icon and label. In each of those, I'm able to specify a label and an icon to show up in My Computer.

My question is: How do I make the drive show two different icons, one greyed out icon when idle and a coloured icon when a card is inserted?