Any doc can be published as a link that needs no account.
Sharing
Open the share dialog on a doc and make it public. You get a link anyone can open.
Readable URLs
A shared doc can have a readable address rather than a random one — worth setting for anything you are sending to a client.
What a visitor sees
The document, rendered as you see it, read-only. Interfaces work: sheets calculate, decks advance, charts respond. Visitors cannot edit, comment or see the rest of the directory.
Turning it off
Unpublish and the link stops working.
Who has published what
Everything currently shared from a directory is listed so nothing stays public by accident.