Geometric paper art by Matthew Shlian.
Rob Ives, paper animation
More paper automata
Reversible paper cubes
A working paper Rubik’s Cube
Intense papercraft examples
Basic popup tutorials
An interview about how popup books are designed, engineered, and manufactured.
Finally, this book is excellent. It explains what you’re doing, how to do it, how to modify it, and ends with a fantastic gallery of popup cards.