e.g. you try changing the log4j levels and nothing happens. Much scratching of head occurs. Normally through frustration you shove a load of System.out.println() calls in your app :)
So the idea is how about being able to do something like
mvn classpath:find -Dresource=log4j.properties
and the plugin would search all the test scoped jars on the classpath, including transitive dependencies letting you know all the jars (and the dependency path to them) which included the resource you specified.
It'd be handy right? Any volunteers... :)