i recently made an angel investment in Huddler.   Huddler easily allow you to make communities to discuss products.  

See their green products huddle.  In fact, if you can get detailed information on the Tesla (this site will make Elon proud).

They just launched Huddler with two active huddles, one on environmentally friendly products and one on mobile products.   given they just launched, they are doing well on the traffic front.