Spell checking should be a default feature in IDEs. I've seen teammates struggle to find the source of a bug, only to find a spelling error in a variable or configuration setting. I'm not the greatest touch typist, and my IDE catches double letters, missing letters, reversed letters and other mistakes all the time.
I remember an old demo that would play a loop of the chorus of I Say a Little Prayer through the PC speaker. It was hard to believe that the speaker could be pushed to such limits.