File systems with version control.. like VMS?
But I think there are two different types of version-control. There's "save it while I edit" draft versions (VMS) and then there's release versions where you do want to keep a snapshot and you might want to email somewhere, in which case, you probably do want to be able to easily see which version you mailed out. Since other OS's and applications may not support version control, you probably do want to support "save as" and you certainly want to purge the old edits rather than sending a file with all the drafts to a customer.
Maybe we need a "save Release version as" to go along with internal versioning?