A tato is a traditional Japanese purse, a kind of container that can be used to store flat items. It can also be used as an envelope, and it is a great way to send invitations.
These are two of my favorite ones:
The tatos in the pictures above were created by Tomoko Fuse. The diagrams can be found in her book Origami Wrappings, ISBN 441630501X (in Japanese).I like these models because, unlike other tatos that are folded with a single sheet of paper, these two models are folded with two. This allows use of the eight corners to create the pattern in the front.
I used 8" (200 mm) squares of Folia Origami Paper, which is the same color on both sides.