Putting your picture into your mail messages

Users of Apple's Mail program are used to seeing pictures attached to people's email messages, but only if they are .mac users.

I noticed a tip on Mac OS X Hints that led me down a path towards installing my picture on my outgoing mail messages, even though I don't use a mac.com account.

The trick: use the terminal to specify a custom header to be attached to your outgoing mail messages. Here is mine, what I had typed into the terminal to add the preference to Mail (while it's not running):

defaults write com.apple.mail UserHeaders '{"X-Image-Url" = "http://www.karelia.com/dan_watson.jpg"; }'
If you have a web site where you can put your own 64x64 image, you can make your image available to other Mac users as well!