Re: password

You can always encrypt PowerPoint, or anything else for that matter, using
an 
X.509 certificate.  Thawte offers free certificates for individuals and
many 
organizations provide their email users x.509 solutions from vendors such
as 
Entrust, Tumbleweed, Verisign, etc.

After an exchange of signed emails, any attachment can be sent securely
with 
encryption, including PowerPoint.

Apple's mail program and Microsoft's Outlook sup****t x.509 certificates
with 
extremely easy to use buttons the end use just has to click to sign and 
encrypt email after the x.509 certificate is installed and certificates
are 
present in the address book (Mac) or contacts (windows).