PGP

PGP? OK so its obvious that you are trying to keep something secret, but you can make a heavily encrypted file with it and the basic version is free.

I would also point out that the independance of anti-virus creators from the OS maker adds to the security of the anti-virus app. How many Microsoft anti-virus apps do you know of? :p It's the same idea as releasing Zimmerman's PGP as open source: everyone could look it over and see if there were any back doors or security holes... Not that I'm suggesting that Apple...

So, if you want privacy you have to crypth every mail. Prefered is PGP. But due to most people doesn't use PGP this is still not a very good option. ...

Mail Loaded PGP 8.0. ...

The "horsepower" of your Mac is not the issue unless you are out of disk space or RAM with a file that big. More likely it is PGP itself. Your best bet would be to check with PGP to see if there are known issues. Also be sure you have the latest version of PGP which is 8.0. ...

I was installing the Gnu PGP tools recently, and stumbled onto a command line tool calledplutil. This tool will parse any selected files and validate them as well formed XML. ...

The only apps that seemed to have "broken" were Little Snitch 1.0.3 and PGP 8.0.3 Freeware which were quickly solved by reinstalling from scratch. Otherwise, it went about as smooth as it could. ...

Makes sense they wouldn't use PGP though, that's now commercial software... ...

Only Mozilla worked for me and I had to add the certificate to Mozilla's security preferences. It then becomes available for use with Mozilla's mail module. After that, I sent myself a signed email. Mail app recognized the signed certificate, but I still couldn't get encryption to work. I've given up for the time being. I'm going to wait until Panther ships. Hopefully...

There's still MacGPG (the GNU version of PGP, I think, in some way). It has a Mail.app plugin afaik. But as I've said: I've never used it... :/ Here's a call: Apple should make security REALLY easy to grasp, i.e.: On first opening Mail.app, it should ask you whether you want to use GPG (or their S/MIME, whatever) and then create everything for you (asking for passphrases...