Swiss army knife by Jun Maekawa

Diagrams in Origami Tanteidan Magazine 67
Diagrams in Tanteidan 2nd convention
Diagrams in The Graceful of Origami by Makoto Yamaguchi
Folded from a square of origami paper

Telescope by Seiji Nishikawa

Diagrams in Works of Seiji Nishikawa by Seiji Nishikawa
Folded from 4 squares of origami paper

Tomb by Nick Robinson

Diagrams in Halloween Origami by Nick Robinson
Folded from a rectangle of Elephant-Hide