These designs are built for mass-production and quick, self-locking assembly (no glue)
I think that the reason I find this site so interesting and fun, is because I think a lot about folding paper.
Custom Paper Toys (the site mentioned above, but re-linked here because that's just the kind of guy I am) is a great, new-ish blog about building toys from paper.
Each month, the author of the blog, Matt Hawkins, designs neat little toys that move, wiggle or otherwise just look plain cool and posts photographs and plans of his creations for the rest of the world to consume.
I especially like Matt's 3D version of 2th Termite from I Am Supel. It's more than difficult to approximate globe shapes with paper and I think that Matt's solution for character's squashed-globe head was very clever (or cleaver as I originally typed--you choose the word that you think fits best).
I find it especially satisfying to see artists and craftsmen use the internet to share their work with others as Matt has with his download-able PDFs.