Best way to do that is with a script. I like this one: InDesignSecrets » Blog Archive » Zanelli Releases MultiPageImporter for Importing both PDF and INDD Files
if you have acrobat or another pdf print driver installed, you could always create a custom page size in the print driver and print to it. enter your scale percentage in id. multiply the dimensions of your page size by that scale amount and enter that number for the custom page size.
be aware that the text will become more difficult to read as the scale percentage decreases.
take care, mike
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