A piloted V1 "Wonder Weapon" (Fieseler Fi 103) .. or a one way ticket to oblivion on a flying bomb as you have to parachute out near the target and I guess you er, walk or perhaps swim back (see below):
A one-shot rocket fighter called the Natter (Bachem Ba 349-A) which is at least armed, something useful when entering the 1944-45 Allied Bomber Stream. Once out of fuel it is a case of parachuting put again and a long walk home (see below)
Are these stange machines partly to blame for the sightings of "Foo Fighters"? Next, how to wind them into a scenario of sorts?