Indiana Jones and the Kingdom of the Crystal Skull (here be spoilers!)

[BenKenobi88]

Desroko said:
And how the hell does covering the skull with a piece of cloth de-magnetize it? I expect this sort of shit from George Lucas and David Koepp, but from Spielberg it's disappointing.

 Well I don't think it ever demagnetized it, it just kept its other...mystical powers covered...because the alien attracted all those bullets (also unbelievable) while covered in the box...