As promised, I've made the Start Screen Saver Example Workflow, as well as the Launch Automator Workflow Mail Rule AppleScript file, available for download to make things easier.
You may have noticed that the example in this article doesn't do anything with message attachments. This is because the Mail rule script we created simply runs a workflow. To process attachments with a workflow, some additional scripting is required. Don't worry[md]I've done this work for you.
If you follow the link above, you'll also find a second Mail rule AppleScript file, named Process Message Attachments with Automator Workflow. When run by a Mail rule, this script will save any message attachments into a Saved Attachments folder within the ~/Library/Workflows/Mail Rules folder, and then pass them as input to your workflow for processing. Don't forget to open this Mail rule script in Script Editor and insert your own security code. Be sure to use a new one, though, so it doesn't conflict with the Launch Automator Workflow Mail Rule script. You'll also need to add a new rule in Mail, and configure it to run the Process Message Attachments with Automator Workflow script when messages arrive with a subject of Automator Workflow and your new security code.
To configure an Automator workflow to process input attachments, just be sure that the first action in the workflow accepts Files and Folders as input. For an example, I've provided a sample workflow named Archive Mobile Photos, which can be used to archive the image attachments from messages into iPhoto.
Ben Waldie, president of Automated Workflows, LLC, is the author of Automator for Mac OS X 10.5 Leopard: Visual QuickStart Guide and the host of the Mac Automation Made Simple video podcast series. For more of Ben's Automator and AppleScript tips and articles, visit the Automated Workflows, LLC website, where you'll also find Ben's third-party Automator actions for FileMaker Pro, Illustrator, InDesign, Quark, Photoshop, Twitter, and more, as well as information about custom AppleScript and Automator development services.