You know those recommendations you get from your favorite websites?  A few come to mind--books from Borders, music from Pandora, just about anything from eBay?  Sometimes they're spot on, sometimes not.  I couldn't have been more surprised when I opened an email a few months ago, and the very first recommended item from Amazon.com was a walker.  I didn't know whether to laugh or take offense.  I'm no spring chicken, but seriously, a walker!!  The thought did cross my mind...nah, there's no way Amazon could possibly know that bilateral knee replacements are common in my family.   

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