Use of non-user readable (null password) private keys

[Piete Brooks]

> It really sounds like you want the extend filesystem ACL provides by
> most commerical UNIXes filesystems.

No.

I want to be able to give `group' or `other' access to capabilities.

I do not want ACLs.

> That would outskirt the whole 'this key is globally public' but granting
> extended rights for limited number of users to use the key.

Nope -- I want to give everyone (or all members of a UN*X group) access.