I have tried this too -- I run multiple monitors, and I want to be able to have ONE sheet of a workbook open on one monitor, and another open on the other. Tired old eyes work better this way sometimes!
BUT... I could not get this to work, and even when I'd tell Windows to set the displays to extended desktop, and manually stretch the EXCEL main window to cover both, I get toolbars and tabs on one monitor, and none on the other.
I tried doing a double-open -- open the file once, then open a second time -- but it opens it in the same main Windows window, does not let me drag it aside as some of these posts suggest.
So I went in to GODMODE, and found the ASSOCIATE FILETYPE WITH PROTOCOL OR PROGRAM menu, and noticed that filetype XLSX was associated with Microsoft Open XML Converter, and NOT with EXCEL itself (like the .xls files are). I changed this back to EXCEL, and
now each double-click on an XLSX file causes a separate instance of EXCEL to start in a separate window.
And... how can I get ONE copy of EXCEL to let me take a SHEET in a workbook and open it in a separate window that I can place OUTSIDE of the Excel window itself (in a second copy of the excel main window)?
I'd also suggest giving OpenOffice.org a try. I find it to be just as good as Excel for all my purposes (and I'm not a spreadsheet lightweight ... I make heavy use of formulas and such), while also providing better and more detailed options and customizability
in a lot of areas. It's more amenable to editing a sheet that's already open somewhere else (it still warns you, but lets you go ahead and do it anyway if you want.)
It also doesn't require running multiple instances in order to have files in independent windows ... by default, each file runs in its own, independent window (not multiple child windows of one main window).
And it lets you painlessly have two sheets from the same file open in multiple windows ... just open up the file, then go to "Window -> New Window" and you have a separate view of the same workbook, in its own full independent window, letting you select
a different sheet, and move it wherever you like. :)
Did I mention that it's also FREE (as in both speech and beer), and is able to read and write .xls and .xlsx (not to mention .doc and .docx and .ppt and .pptx files) files seamlessly?
The only reason I use Excel at all is because I have an old copy of Office 2000, and it happens to open and run very snappily on my slower hardware. But if you're using newer versions of Windows and Office anyway, there probably won't be much performance
difference between OpenOffice and Office.
It may not have as many wizards and things for advanced charts as regular Office, but it's a stable and mature product that's under constant development, so features are improving all the time. And it handles everything I've ever needed to do over the
last 10 years more than adequately (in some features and instances, better than regular Office--like saving and importing from custom text-delimited formats, find and replace with regular expressions, and allowing saving of images out of Office files, since
some people insist on sending me images embedded in Word docs and Excel files and the like :) ).
Open Source Software FTW!!! :D