Just discovered something horrible which OpenOffice does. Ordinarily, in MacOS, you switch between windows belonging to a particular application by hitting CMD-`; this is standard and handy and part of the windowing system, and I've never seen any application not honour it.
Until now. Using OpenOffice for Mac, CMD-` changes from normal to scientific notation in spreadsheets; they've hijacked the normal behaviour. Horribly annoying, and no good reason whatsoever for it. Grr.