The following site has some useful information regarding resizing your files.
See http://www.contextures.com/xlfaqApp.html#Unused
There's also other useful stuff out there as well.

Signature
Kevin Backmann
> Hi!
> I work with VERY LARGE files, some will not work as attachments on email. I
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> ENJOY YOUR WEEKEND!
> Gene:)
widman - 30 May 2008 22:14 GMT
Winrar is very effective in reducing excel file size for emails. It will
generally take a 6 MB excel file to about 1.5 MB
> The following site has some useful information regarding resizing your files.
>
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> > ENJOY YOUR WEEKEND!
> > Gene:)