I had an employee come to me with an unusual Excel workbook question. If he
has two workbooks open, they appear on the task bar as two separate
documents, but when he has one of them open on his desktop, they are both
open in the same Excel interface, so that when he closes one, the other is
still open behind it. He wants to know if there is a way to keep them as two
separate documents without any interface connection. I'm not sure of his
purpose in wanting to know, but I told him I would ask the experts.

It's an interesting question because I know that if you have two workbooks
open and you make changes in one then go to the other and make changes in it,
as you hit redo, the Excel interface remembers all the corrections between
the two documents and will jump the redo from one document to the other...so
in essence, as long as they are both open, they are connected in the the same
Excel interface.

Any ideas or suggestions, or can it even be done?