The wreckage of TWA Flight 800, which was reconstructed for the investigation and then used for NTSB training, is going to be destroyed. They say its use for training was with the stipulation that it would never be used for exhibit or public display.
I'll admit it is a somewhat ghoulish sight but they could create a lasting memorial if they'd turned it into something similar to the Museum for the Memory of Ustica in Bologna which is one of the most haunting museums I've ever seen.