What are the best Room Accustic Treaments members have found?

I  am looking into adding some room acoustic treatments to my room.  I am just looking for advice on some simple room treatments that fellow members found worthy of purchase. 
tuberist wrote:
davidrolson, forgive me if you already know this. Room treatments generally address damping (absorbing) or redirecting sonic reflections. if you do some research, you'll have a good handle on what your room "needs" Many of us have made absorption panels with OwensCorning foam insulation installed in frames with nice fabric covers. It sounds like you've made the first step to realize you want to treat your listening room; many never do that and IMO that's the primary building block to a good listening experience. Good luck.
I agree with tuberist's comments as cost is a big deal to me. FWIW, I have about $22,000 of stereo gear at list price that cost me about $7,000 used. Never bought new. I looked at GIK pricing and figured I could save half by doing it myself: make panels with Owens Corning absorbing material, lumber for frames from Home Depot, and fabric from Joanne's Fabrics.

Now would these go in a formal living room? Probably not. Would they do well in a well decorated man cave? Probably; I know I am happy with the result.

Also, my personal opinion is that foam products do not work as well as Owens Corning (or Roxul Rockwool) because foam has have lesser absorption properties.

All sorts of questions to ask yourself!

Thanks for listening,

Just installed GIK diffusors and they work great.  Addressed some smearing and focused up the vocals.  Bit more control of bass.  I also have 6' quarter round ASC treatment in the corners.
There are many great acoustic treatment companies and products out there, but one I am fond of and have worked with at some shows is Acoustic Innovations. They are American Made products, great people to work with, and have very visually appealing products. Much of what they do is theater oriented and they have an incredible client list that they can't publicly disclose.