Jon Udell describes how David Rumsey was a hit at the Open Source Convention. Rumsey is making a large number of rare maps accessible through the Web instead of sending them to a museum.
The part that caught my eye was the use of a browser based image viewer that allows the digitized maps to be annotated with good old URLs. At the end of my CMS class this spring that soon (next 2-3 years) photos would become real first class citizens on the web. You'll be able to distinguish a photo URL from a generic image URL, pull metadata from photo URLs, and be able to manipulate photos through REST style APIs. Of course you can substitute digital image for photo, but the consumer camera market combined with explosive camphone adoption makes this a no brainer.
Too bad the image management, tiling, and viewing software that Rumsey uses isn't open source, as far as I can tell.