email resume Word or PDF for resume attachment

I use RTF format.  That avoids any problems or questions due filtering for Word viruses, and it's a lot smaller than a PDF.  It's also viewable with any word processor, including the minimal Wordpad that comes with Windows.  I remember one place I submitted my resume to several times in Word's DOC format, at their request, and each time it got filtered out (even though there was no virus in it) because their email was set to delete all .doc file attachments.  It went through fine as an RTF.