Gyroplanes, autogyros or whatever you call them, thingies with a thrusting engine and an unpowered auto-rotating rotor, were actually developing into quite useful objects until the helicopter came along and took over. "Jump-start" allows VTO and they can land vertically quite well as long as the disc loading is not too high, and the lack of a high-torque full-time transmission makes them small and light.
Believers like Groen Brothers Aviation think that the gyroplane never really got a fair shot, and that it's actually a cheaper way of doing a lot of helicopter missions. The only thing it really can't do is hover.
The infamous Rotodyne (gyrodyne) was basically a gyroplane plus a tip-jet drive system that allowed it to hover and do VTO/landing with a higher disc loading. It's being revived by DARPA and Groen Brothers as the Heliplane.