Re: Opposite effect
Knew a guy who appeared to have the ability to curdle milk. No hot drink made by him was ever drinkable, there would be unidentifiable scum floating on top even when you watched him do everything in the normal fashion.
Another guy I worked with had the abililty to make any screwdriver, pliers, scissors - well, basically, anything metal he came into contact with - start to rust within a couple of days.