Origami boxes with photo tutorial. Diagrams here: http://www.duitang.com/people/mblog/64700164/detail/ Letter sized paper (8.5" x 11") made a cube-ish (7cm x 7.5cm) shaped box. A4 sized paper made a rectangular box. Letter paper folded lengthwise made a 6.5" X 2.25" box.
Icosahedron Modular Origami
Create your own nerdy icosahedron with some simple modular origami. Ok, technically it's not "origami" origami because the units are made of rectangle pieces of paper but if you call it origami I won't hold it against you :) It can take awhile to fold all the units for this little guy but I think the end product is worth it.
ひな祭りのひなあられ入れに使える！ひな壇にも飾れるお花の紙皿の作り方 | CRASIA（クラシア）
origami gift boxes
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