So tonight on a whim I took a last minute proofreading job, expecting it to be a random college kid with a history paper to be checked for grammar goofs. Half an hour of work, tops.
Turned out it was a programmer with an unfinished product evaluation, needing technical writing pointers (first rule of technical writing: draw attention to the most important thing. If it really matters, it is first or last, visibly separate and easily legible) and some coaching on how to formulate her recommendations and conclusion. Three hours of interesting and challenging work, concluded with advice on what to do to polish her writing skills.