I use FoldersSynchronizer to keep my data and work files synchronized between my office iMac and a 4 gb USB drive - I sync at work several times a day, then sync between my USB drive and laptop at home if I need to do work at home. I had some problems in prior versions with sync of packages, but this appears to have been resolved with the recent upgrade. Over the past six + months it has worked reliably and consistently and keeps my life better organized. With the most recent upgrade it also seems to run much faster. For my needs, it runs great. The documentation is quirky but when I had my problem with packages got fast feedback from the developer.