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.
Picture of Countertop Greenhouse Designed to help 4 small pots in a herb garden grow on the bay window. Made out of simple wood, vinyl and hotglue, all parts cost less than $20 and can be picked up at various big box stores.