For a server I help maintain, we like to publish the results of the last build
that passed all its tests, so we point clients to

http://deadlock.netbeans.org/hudson/job/nbms-and-javadoc/lastStableBuild/artifact/nbbuild/nbms/updates.xml.gz

The project configuration GUI has an option

"Discard all but the last successful artifact to save disk space"

We would like to save disk space, but this option is useless for us: if a build
completes with some test failures, Hudson would delete the artifacts from the
stable build preceding it, breaking the link!

What we would like is a similar option to keep just artifacts from the last
stable build. Alternately, modify the behavior of the existing option to always
keep artifacts from the last stable build, as well as those from the last
unstable build if that is newer (since you might well want both to be available).