Writing for effect
You got me on the first. I have trouble with affect and effect, and still have to look up usage notes (which I have trouble distinguishing). Within arm's reach I've got Webster's Ninth Collegiate and Fowler's Modern English Usage. My practice has been to affect a usuage in which effectively only effect is effective use. Note that affect has a verb form, though the usage is different from that intended here, and might itself be considered an affectation. More confusingly, effect, usually intended as a noun, has a verb form, the effect of which is to effect a confusion in the use of affect and effect, a trait which affects me as well.
You're wrong regarding impact. It's a verb (transitive and intransitive), as well as a noun, according to Webster's. Though the common usage of it (particularly in business speech) impacts me all wrong,
