I have a folder that, besides other things, has folders named after dates, e.g. 20110908 20110909 and so forth. Every night, I would like to run a tool that checks for all folders matching that datemask (could be 201*), and bzip2 any of them that don't already have a similarly named bzip2 archive. And ideally, if after bzip2-ing the folder contents change, I would like to re-bzip2 them.
Is there a tool out there that would help me?