Example 1. I'm in Publisher (which is actually quite a respectable simple vector layout package, but I digress) and I go Insert / Picture / From File... and the Open dialog appears. I navigate to the folder where the image I want is, and then suddenly remember I needed to touch the image up in Photoshop before I place it into Publisher. So I right-click and choose Open With... Photoshop. I touch it up, save it, and Alt-Tab back to my File Open dialog, pick the newly edited file, and click Open. If I didn't have that facility, I'd have to open Photoshop, navigate to the folder, edit, go back, etc... meaning TWO navigations rather than one.

Example 2. I'm attaching a PDF to a mail message so I've got the Open dialog up, but I can't remember which is the right one. So I right-click and choose Open With... Acrobat to check. Same result -- one navigation instead of two.

Example 3. Insert / Picture / From File..., and I realise I want to create a text file for notes in that folder, so I right-click, New, Text File... and then right-click the new text file and Open With... Textpad.

Example 4. (good grief man, get on with it). Any File / Open dialog, and right-click a file, Copy, then Paste, to create a copy, rename it with a single-click, then open the copy.

You get the picture.

In practice I use this or some variation of it fairly infrequently compared to the number of times I use File / Open (etc) *without* using it, but it's still perhaps 5 or 10 times per work day. So it's hardly a drastic timesaver, especially once I'm quicker at navigating around Finder, but it'd still be very nice -- I badly miss it.

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