I have seen or heard first hand of many (almost all) of these "in the wild"
being used
https://cwiki.apache.org/confluence/display/KAFKA/Clients#Clients-For0.8.xin
production somewhere.

/*******************************************
 Joe Stein
 Founder, Principal Consultant
 Big Data Open Source Security LLC
 http://www.stealth.ly
 Twitter: @allthingshadoop <http://www.twitter.com/allthingshadoop>
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On Tue, Apr 15, 2014 at 10:22 AM, Jonathan Hodges <[EMAIL PROTECTED]> wrote:
 
NEW: Monitor These Apps!
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