Wacko Nissan Concept Vehicles...

 Nissan Prince Sprint 1900 Prototype, 1963

I don't think this is an encyclopedic list but it certainly is a substantial one.

Here are, in chronological order a great number of Nissan/Infiniti concept vehicles.  While some are purely paper exercises and never had a single part manufactured for them, others made it all the way to living, breathing, running prototypes.  Note that a LOT of design features from these prototypes made it into real world production vehicles for Nissan.  For example--take a look at the downward sloping roof line if the Mixim from 2007.  Though it looks odd then and now it is EXACTLY what can currently be seen in not only the new Nissan Juke but in something like the Kia Soul as well...



 Nissan 126X, 1970

 Nissan 270X, 1970

Nissan 216X, 1971

Nissan Skyline Concept, 1972

 Nissan AD-1 Concept, 1975

 Nissan NX-21, 1983

 Nissan CUE-X, 1985

 Nissan Boga, 1989

 Nissan Figaro Concept, 1989

 Nissan FEV, 1991

 Nissan AP-X, 1994

 Nissan TrailRunner, 1997

 Nissan KYXX, 1998

 Nissan Jikoo, 2003

 Infiniti Kuraza, 2005

Nissan Zaroot, 2005

 Nissan Terranaut, 2006

Nissan Mixim, 2007 

 Nissan Bevel, 2007

 Nissan Pivo-2, 2007

 Infiniti Essence, 2009

Nissan Land Glider, 2009