Web 2.0 Stores > Fast, Simple, Search Engine Friendly Ecommerce

Dare Obasanjo pointed to Julien Couvreur's blog post that discusses a Cross-document messaging hack that both Dojo and Windows Live platform came out with:

The Dojo and Windows Live Platform teams have both recently released DHTML hacks that allow two iframes in different domains to communicate, bypassing the notorious same-domain policy implemented in browsers. I'm surprised by the relative lack of response in the AJAX blogosphere, as this opens lots of possibilities for mashups.

The basics:

The hack relies on dynamically created iframes, using the fragment identifier to leak/communicate information to the other domain and timers to check for iframe changes.
For example, if you have page A containing an iframe B in a different domain, then B can create a new iframe and load it with a url in the same domain as A.
The url that is loaded doesn't generate a request to the server if it is properly cached and only the fragment identifier is used to pass changing information. Page A can now get the DOM handle on the new iframe and successfully retrieve the information transmitted in the url by B.

Julien finishes up with a question to the community: "Now, the question is what cool applications will you build with this new cross-domain capability?"