The Hard Rock Memorabilia exhibit is a great example of what becomes possible now that Seadragon Deep Zoom is integrated into Silverlight 2. The exhibit includes:

Madonna’s page in her high school yearbook:

Pat Boone’s shoes:

John Lennon’s handwritten lyrics to Imagine:

And there’s much more. When you choose subsets — by artist, decade, type (e.g. clothing, instruments), genre, location — the images retile, and they’re all navigable using Deep Zoom’s extreme zoom and pan capability.

Note that the links above lead directly into the exhibit and focus on the indicated asset. You acquire these from the Share link in the right pane, which exposes URLs of the form:

http://memorabilia.hardrock.com/Default.aspx?AssetId=8191

(or just http://memorabilia.hardrock.com/?AssetId=8191)

It’s great to see this permalink feature included. Deep Zoom is going to open up vast spaces for exploration, and in order to explore those spaces together we’ll need shared coordinate systems.

To that end, I’m hoping that future incarnations of this sort of exhibit will expose richer URL namespaces. If I want to show you Madonna’s yearbook in the context of the 1970s, I have to tell you to click Decade, then 1970, then choose the 2nd item in the 3rd row. It’d be great to be able to get you there directly:

memorabilia.hardrock.com/decade/1970/20352

And of course I’d want to locate Madonna for you, among her other classmates, by zooming to the desired view and then tacking those coordinates onto the URL.

If these precise locators are made available, conversations about the views they identify can form on the web. To see why it’s crucial to expose a public namespace, consider the David Rumsey map collection. There you can explore and precisely annotate an extraordinary collection of historical maps. And you search for those annotations within the Java-based viewer. But when you annotate a feature within a map, it doesn’t — so far as I can tell — produce a shareable URL. If those URLs were available, the collection would be woven into public discourse to a far greater degree than it is.

A couple of years ago, I asked whether rich Internet apps can be web-friendly. One of the reponses came from Kevin Lynch at Adobe, who made this example showing how navigation within a Flash exhibit of images can be reflected on the URL-line.

I don’t think it matters much whether you expose the RIA’s state on the URL-line or by means of a permalink. What matters is that you do it, and do it in as granular way as makes sense for the application.

PS: For extra credit, it’s nice to provide the underlying data for this sort of exhibit. When you’re exploring the Cubism timeline, for example, you can grab the data and mix it as you please.