Or, does anyone happen to know where Castor in particular has gone, if it's still going to live somewhere? Its source is here but without any helpful additional info: https://github.com/codehaus/castor
Codehaus' blog post about their history and the shutdown, for reference: http://www.codehaus.org/about/history.html
Edit: The comments here https://news.ycombinator.com/item?id=9161562 imply that when they announced the shutdown, they said that project SVN:
Will all be migrated to Github - SVN repos will be migrated to Git and transferred into the "codehaus" Github account. This is a readonly account. Inactive projects may be migrated ahead of the shutdown.
And thanks NealC for pointing to this tweet that indicates that nexus.codehaus.org will continue to be available after the shutdown. https://twitter.com/codehaus/status/594042932107186176
TL;DR: Source is now on github under the codehaus account, and the maven repo is still available.