Found a microsoft fix-it to open EXCEL in multiple windows. This is especially useful if you are using multiple monitors and/or require side-by-side comparison of some documents.
Note that it requires changing some bits of your registry. I used the Fix-it link, which works like a charm, so I would recommend that lest I mis-perform a step and mess up my registry. Especially since I am doing this in the morning, with a tad of grogginess.