Compress large Office files with embedded images

I run into a user that had an Excel file that was 114688KB in size and wondered if it was possible to make it smaller. In Excel, Word and PowerPoint there is a command to compress embedded pictures. Open the Picture toolbar and click on Compress Pictures. It does the following:

• Reduce resolution (to 96 dots per inch (dpi) for Web and 200 dpi for print), and unnecessary information is discarded.
• Discard extra information. For example, when a picture has been cropped or resized, the "hidden" parts of the picture are stored in the file.
• Compress the picture, if possible.

After that the Excel file went down below 1000KB.