SpaceGuard SRM - Disk Quotas Manager 

SpaceGuard SRM is a directory based quota management tool featuring quota enforcement, notification through popup and SMTP/MAPI mail, and Active Directory integration.
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User Management Lite - Windows Users Management Administration 

UserManagemeNT Lite is the free version of UserManagemeNT Professional, featuring advanced user creation for Windows NT and Active Directory networks including user resources.
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User Directories for IIS 

User Directories for IIS is an IIS ISAPI Filter DLL that web enables your Windows user accounts. This functionality has long been available on UNIX platforms and now it is available for the IIS web server.
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