Product review (4 stars): I got better pours but still had a bit foam at the ...
Works fairly well in cooling the tower of my kegerator.  Previously, I was forced to run about 4 oz. of beer off with each fresh pour because the temperature in the tower wasn't keeping the beer cold enough and I would get glasses of half foam.  This seems to be very common with low end kegerators.  I read lots of forums and did lots of tweaking to the temperature/pressure/lines/etc., but didn't have any notable success in reducing the foam on each new pour.  After installing this product, I got better pours but still had a bit foam at the start (probably a 50-75% improvement).  I went to my local big box hardware store and got some pipe insulation, which wrapped around the outside of the tower to keep the cold in.  Now I'm getting perfect pours every time and not wasting any beer.  This is definitely a recommended product for those frustrated with foamy keg beer and adding in some insulation will help if this product doesn't do the trick by itself.

There are lower end version of this product (and DIY tutorials) that use computer fans and/or 9 volt batteries, but do NOT waste your time.  These products don't cool near as well!