Mac OS X (Tiger) contains many useful PDF functions as a core component of its operating system. On the print menu in every program is a PDF drop down menu that gives you options to save, fax, and/or email any document in PDF format. This option is available with word processing documents, photos, and web pages (full or partial). 
Here is a screenshot which shows the PDF drop down menu and the various options it offers:
I use the "Mail PDF" function all the time, as it makes it extremely easy to email a copy of any documents to my clients. One nice feature is that when you select that option, Mail automatically opens with the PDF inserted, saving time and energy. Also, the PDF that is created is sort of a "temporary" type file, in that it can be emailed and used by the recipient, but you do not have to save it anywhere. Clients love being able to receive updated information so frequently, and I love being able to do so so quickly.
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