I like open note exams (and perhaps open book exams, as you need to know the book well to know which page to look at) - it forces you to condense the material to the salient points and operationalise it to solve what would be more challenging problems than a simple recall exam.

When I see 'cheat sheets' - designed to be hidden on the back of calculators or whatever - then I see true application of human ingenuity and intellect.