ExcelSpyGlass is an Excel addin that allows the user to view one or more cell ranges in one or more separate windows while working with other Excel worksheets either in the same workbook file or in a completely different workbook file.
All ExcelSpyGlass windows will be in view until closed during an Excel session, allowing for simple, visual comparison from one worksheet to another or the ability to reference data from one or more worksheets while focused elsewhere.
An ExcelSpyGlass window presents a selected cell range as it appears on the worksheet, with respect to the format of each individual cell within the selected range.
There is no practical limit to the number of ExcelSpyGlass windows that can be open simulataneously. To install, unzip to a folder of choice and follow the instructions found in ExcelSpyGlass.