Ready Mech

Print, cut, fold. Monsters, robots, etc, all from an 8.5"x11" page.

dead link: http://readymech.com/

Haunted Paper Toys

Lots of cool goth/Halloweenish paper projects to print and assemble. Files are MS Word documents, rather than PDFs or plain images however.

Link

Money Wallet

Modular origami of a sort. Twenty bills folded in two groups to make a wallet for holding more money. With instructions in a wordless form eerily reminescent of Ikea assembly manuals.

Link

The Elements of Pop-Up

This book for "aspiring paper engineers" provides an encyclopedia of pop-up effects each with explanation of how it works. The more complicated effects which benefit from a model that can be disassembled are not glued shut allowing the reader to open them up to reveal the inner workings. The opening page has a very dramatic monster which serves to illustrate many of the techniques combined for a single creation. The ending page gives an overview of the steps to publish a pop-up book.

I've found this helpful in designing pop-up cards, which I make as one-offs.

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