I was looking through my  Aircraft books and i stumbled upon a few that i think would be very nice to have in FS.

The first is the Mustang that was supposed to be used on carriers. It had an arresting hook, folding wings, along with a Water/Methanol Injection.

The Second is what is called a sea mosquito. About 12 were made at the end of WW2. I dont know how or if any still exist. They were about a foot shorter in all directions. The wings folded in two places to get space (the wings folded halfway down the span, then the wingtips folded in the opposite direction).

The Third is the the first North American OV10 Prototype.
What differed this model from all the others is that it was a biplane and could be used on a carrier. I think it was the secretary of the navy that didnt like the design. He said "we are operating a MODERN Navy, we have no need for biplanes."

The Fourth and Final one, is the Skyraider Airliner. Douglas removed all the electronics and weapons out of the fuselage and could fit 10 people, their luggage, and a working, yet small, bathroom. The only difference on the outside is that it has windows on the side and a double door on the starboard side of the fuselage.

Try the Horten aircraft, those are cool