I recently ran into a problem where in certain situations Search would do the "searching instead for x" because it assumed I had made a typo.
I had in fact not made a typo, but it would be nice to (similar to an autcorrect in a keybaord app) be able to specify a list of words that should never be autocorrected.
The example in this case was Panoramax (which obv tends to get autocorrected to Panorama).
I'm sure there other people with similar word problems
