if we're talking about classic aerodynamic lift-based type of flying, flying without wings is probably not an efficient proposition unless you are flying really fast or at very high dynamic pressures anyway, at which point you can probably rely on body lift. The Rockwell penetrating bomber platforms, with oblique wings come to mind. Because they were flying fast at low altitude, they could pivot the wing along the fuselage and get great gust tolerance among other things. At low speeds, if you don't have some sort of spanwise distribution of lift, induced drag is a killer.
More generally, I guess much depends on what you call "wings". Even in the Rockwell bomber case, the fuselage happens to be a long, thin flat structure you could still call a "wing". Anything that generates aerodynamic lift by generating a pressure differential between its lower and upper surfaces could be a "wing".