I'm fairly certain that you can get a Fedora machine to *authenticate* against a domain controller, at the least. Active Directory is a form of LDAP, so in System Settings->Authentication, you can try LDAP. I think that the Base DN is ou=Users,dc=(yourhostnamepart1),dc=(yourhostnamepa rt2) where your domain is: yourhostmanepart1.yourhostnamepart2.
However, instead of "uid," active directory uses something like "sAMAccountName".
I know that Win2K, at the least, was also capable of doing Kerberos with some settings changes.
Finally, you could try SMB authentication.