This script is based on some of the ideas and code from Sal Soghoian's excellent demonstration of the new Preview fingerprinting feature in Aperture 2.0.1. Basically, all Previews generated in Aperture 2.0.1 and above have the image version ID of the originating Version embedded in the IPTC Special Instructions tag. Grab that Version ID and you can have fun showing the Version in Aperture, exporting it or whatever.

Podcast discussion from Inside Aperture.
The full Aperture-InDesign Integration sample. Make sure you watch the Fingerprinted Previews explanation movie for ideas.

Rather simpler than Sal's example, this strips the required code down to the bare minimum for people to build up from. All this one does is let you choose a file, and if it's a Preview from Aperture (dragged out into the Finder etc.) then it will reveal the original in Aperture. I've also attached a droplet version which will do the same for an image dropped on it.

Of special note to scripters is the method of getting the IPTC tag from the file - this is copied directly from Sal's examples, and uses Spotlight to extract the tag value - no third-party stuff like EXIFTools required.

For true weirdness (Leopard-specific), run the script in Script Editor but instead of selecting a file normally, open up the photo browser from the bottom of the sidebar and pick a Preview direct from Aperture, then get taken to the original!

Aperture 2.1 or above required, and make sure that you've updated any Previews generated in older versions of Aperture.

Ian