CachingResourceManager whitelist/blacklist for paths or extensions

I don't know if this can be done without adding a significant performance overhead, but it would be handy to be able to set a whitelist or blacklist for the CachingResourceManager to control what paths it cached.  Either configurable by extension, or a wildcard path matcher.  I would want extensions to be case insensitive and allow paths to have the ability for case insensitivity.  

Examples:

• Only cache txt and jpg extensions (whitelist)
• Cache everything BUT json files (blacklist)
• Only cache files inside the /images/* and /css/* folders (whitelist)
• Cache everything BUT paths matching /dynamic/.txt* (blacklist)
• Cache everything matching /images/* and /includes/* but don't cache *.js (both whitelist and blacklist)

These are just some ideas.  I'd love feedback.