Like origami for instance, I've written about origami several times--the most recent in October. Have you heard about the origami space craft? I heard a brief mention on the radio and then found this article. Sounds crazy, but a lot of what we take for granted now, originally started as someone's crazy idea!
Most of us have grown up folding paper airplanes, and the interest in doing so, is evident in the number of paper airplane books we have in our collection, from Super Simple Paper Airplanes by Nick Robinson [745.592 ROB] for adults, to the children's book, Flying Things by Michael DiSpezio [J 745.592 DIS]. Flying Things not only gives paper folding instructions, it teaches the physics of flying! The folding of paper airplanes even has its own name--aerogami!
Fabric folding is also a craft that is gaining in popularity. Wagashi: Handcrafted Fabric Art from Japan by Kumiki Sudo [741.572 SUD] has some instuctions for fabric folded items. (Also look for Sudo's Omiyage: Handmade Gifts from Fabric in the Japanese Tradition [745.0952 SUD] which has some stunning gifts reminiscent of paper folded flowers and cranes.)
If you need a baby gift idea, look for Baby-gami: Baby Wrapping for Beginners by Andrea Sarvady [649.122 SAR], described as "origami meets the age-old art of swaddling." The book is a delight if for no other reason than its colorful pictures!