Create small "drill down" displaced ranges for quick sums, subtracions, etc
I worked with old time accountants that would add numbers on the side and then key them into worksheets creating cursed mystery numbers lacking any reference in the worksheet they created thus also creating a nightmare for future users
So I've always thought it would be nice to be able to have an option of creating a mini sheet within a sheet (a quick automatic link to a range in another tab containing quick calcs). So maybe entering two equal signs ( == or something) a two or three column 10 line pop up grid would appear. Users could plug in their numbers and any simple references and this information would be saved somewhere else (say a tab dedicated to such little side calculations). Naturally, just the formula and/or result would appear in the cell itself just as with say =10+20+30. Instead maybe it would look like ==[link] or =a10+a50-[link]
I know notes can be entered following a formula with a colon or something I believe. (Havent used it in years)
I like it. I'd like it to work perhaps as a format option, turn it on and give it a range elsewhere in the spreadsheet, and when one clicks on the cell, a floating window pops up showing just the range: just the range, not its own Ribbon, et al., and not as a current style Pane, just a floating window showing the range and its contents, functioning as a little scratchpad as it were.
That way one COULD keep detail in a separate section of the spreadsheet dedicated to proper structure and storage of the detail while at the same time maintaining ease of use for all (not least, bosses who are flat not interested in moving past the "light user" stage).
No hunting about for the particular source of the result in the cell. Just clock on it and the range in question pops up as a floating window above the current sheet, trapped in that spreadsheet of course, not an independent window, and not forced to obscure any bit of the rest of the current sheet the user wishes to see because he can move the scratchpad window about. Oh, and it would stay on top until closed, obviously. And I think closed on purpose with its "X" button, not (being fancy) automatically by clicking a cell other than its result cell.
And it could even simply be just a wee scrap of spreadsheet to do off-the-cuff writing and calculating. I will ask: how many times have your users (bosses, not-a-boss-but-still-a-dufus, etc.) done just that, writing in their own calculations, even overwriting other things to do their own scratch work ("Typing over that cell didn't change the part I cared about so..."), and in so doing broken the spreadsheet, saved it, maybe even a few times in different places, and then come complaining to you? Even if not structuring things while still offering easy inspection of what makes up a result shown to the user, just wanting a scratchpad, this would be quite useful on its own, and rather invaluable in building proper structure and data handling into a spreadsheet that is going to be used by people who simply aren't going to know spreadsheets or value the idea that they have to hunt around and so on.
Kenneth Barber commented
You can use a normal sheet for side calculations! I don't see any reason to have a special type of sheet. I can also see the problem of people wanting to reclassify "quick" calculations as permanent calculations.