Yes.. Its possible
Well.. Billy might not have thought of it, but yes, its possible.. For this u must have the NTFS file system in ur OS. You can then provide file level permissions to specific users. Also u can limit even the other computer administrators by giving them specific rights.. For example, in my computer i have 2 computer administrators as well. I have full access 2 everything.. But the other administrator is restricted from certain tasks like system date change, deletion, creation and modification of files from certain partitions, accessing the CD ROM drive, accessing my personal documents.. Etc.. All this and more is possible by providing rights 2 certain services and revoking some permissions.. But NTFS file system is a must for all..