Hide a partition in Vista

Anyone know how to hide a partiton or drive in Vista without just disabling the controller it is attached to?? Any help appreciated..

I wish to isolate the 2 OS's from each other as much as possible.. I don't want either to have access to the other's C: drive..
I am using an alternate dual boot strategy.. I use my escape key to decide which drive I boot from, (an option on some mobos)..
Vista has it's own drive, Xp has another.. I hid the Vista drive from Xp by disabling, (in device manager), the controller channel the Vista hd is attached to.. That is not an option in Vista because the Xp hd has a partition I want Vista to have access to.. Again any help would be appreciated..

Right click my computer, go to manage. Then on the left hand side go to disk management. Or alternatively, in the search box at the bottom of your start menu type diskmgmt.msc and hit enter.

On the right hand pane, (no right hand pane if you accessed the .msc directly) right click on the partition you wish to hide, and click change drive letters and paths. It should prompt with the current drive letter assignment. Then click remove. It will warn you that some applications blah blah blah won't work. Just hit Yes.

Note you cannot hide the drive letter if it is the system volume, no shit right?, nor can you remove it if it is hosting the pagefile...

Thanks.. Worked out the way I needed it too..

Thank you very much. I have Vista on one partition and Ubuntu on another, and sometimes when I'm in Vista I wonder what that E drive is. Whenever I click on it it would say the drive needs formatting, and I'm afraid that one day when I'm just out of bed without a clear mind I'd just format it. Thanks for this solution.