While discussing the Jurisdiction Database, the topic of programmatically extracting sections of CC license legalcode came up. This would be used, for example, to link to specific sections of the legalcode, or compare specific sections of two different pieces of CC legalcode.
Nathan Yergler prototyped some XPath-based extraction, and it appears that heuristics can be developed to support this. The ideal implementation will include a library for performing the extraction, and a web based interface for displaying extracted results side by side.
The very rough prototype can be downloaded from http://labs.creativecommons.org/~nathan/source/legalcode-prototype.tar.gz.