Although, more impressively, an Israeli AF F-15 really did land with a wing missing, which is what i thought this thread was going to be about when i saw the heading.
There was also a DARPA F-18 that was used for adaptive flight control logic. As I recall the F-18 had a wing that folded to simulate battle damage and real-time flight control logic adaptation to compensate using other aerodynamic flight control surfaces and assymetric thrust vectoring.