Fellow forum member Pablo J. Alvarez at What if modellers forum has an incredible website for imaginary aircraft and really does a fantastic job!!! It's http://www.fantasyplanes.com . The texts are in Spanish but it's really the projects themselves that will make you add the site to your faves immediately if you are a real aircraft enthusiast...

Allow me to share this amazing project with you. Pablo's concept was to create an autogyro with a 1000 hp engine. To him, the autogyro is the perfect air utility. Easy to fly, fast and able to land on a ridiculously small area. He regrets that this economical way of flying has not been applied to our modern aircraft. "More than a model, it's almost a sculpture. I ask you to be forgiving with the work's shortcomings, because what matters is the fantastic concept behind it." Sure, Pedro!

There is also another fantastic autogyro on Pablo's site, this time based on a U.S. Navy Boeing F4B biplane, but I'll let you go and see for yourselves... You won't regret your visit!