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We'll use a feature in the just introduced Google Docs & Spreadsheets Suite that lets you create new online documents by emailing them directly to a secret email address. The documents can be sent as an email attachment or even as a rich text email.
Here's a step by step approach to creating PDF file from your rich-text email messages or a Word document using Google Docs [support for spreadsheets is expected soon]
Step 1: Assuming you already have a Google Account, get your unique email address here where you'll be sending the documents. [under Email-In Your Documents or Files]
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Step 2: Using GMail, Outlook or any other email service, compose a new email message. Either attach your Word document or create a rich-text email message. Send this email to the address you copied in step 1.
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Step 3: You will soon receive an email message back from Google Writely containing a link to your document on the Google Docs server. Open the document inside Google Docs.
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Step 4: This is the last step - click the Google Docs File menu and choose Save as PDF. Select any folder on the hard drive and your PDF is ready.
The whole process takes less than a minute.
Quick Tip: You can also use the Google Docs email-in feature to upload more than one document in a single email message.
Related: Convert PDF, Excel Spreadsheets or Word Documents to HTML