Revision Control
Subversion
A conventional central repository system, but has the virtue of
being HTTP-based employing WebDAV and DeltaV.
Darcs
Darcs is a distributed vcs written in Haskell. It looks very interesting as it will probably fit very well with Harmony (even though Harmony uses OCaml).
Git
Git is another approach to decentralized vcs.
RDF
DBin
DBin
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GVS
http://gvs.hpl.hp.com/application/about-gvs
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They have an application demonstrating it: GVS
Browser.
Articles
Manage source code using Git
Harmony
http://www.seas.upenn.edu/~harmony/
The Harmony system is a generic framework for
reconciling disconnected updates to heterogeneous, replicated XML
data. It can be used, for instance, to synchronize the bookmark
files of several different web browsers, allowing bookmarks and
bookmark folders to be added, deleted, edited, and reorganized by
different users running different browser applications on
disconnected machines.
Hypertext Versioning (Versioned Hypermedia) in Molhado
A XLink-based scheme for a graph of revisions. http://home.eng.iastate.edu/~tien/molhado/vh.html
Related
http://en.wikipedia.org/wiki/Unison_%28file_synchronizer%29
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Articles
"A Theory of Compatible Versions" by David Orchard
in XML.com.
The Source Code Management for OpenSolaris pages discusses their
selection process and includes review/comparison of Git and
Mercurial.