Printing an A5 booklet using A4 paper

Well, I've just been dealing with what turned out to be an eight-page booklet – and got away with leaving the printer to do the work, by selecting 'booklet' as the layout option. Another approach I've heard mentioned is to use an imposition tool (Quite Imposing is a name I seem to remember) on a .pdf

I suppose it might be possible to set up a number of different frames and tweak the linking, but I think I'd prefer a solution where rearranging the content to match the page-order of the output was something I didn't have to think about :-}