This picture illustrates my awfull room. The picture was actually taken from the kitchen (notice frame on right side of photo). As you can see my couch setup is less than ideal, and my room is almost perfectly square (17'x18'). I end up moving furniture around if I really want to get into something. There is the WAF factor to deal with, but I'm open to suggestions...

The panels are acoustic tiles covered with burlap. There are 8 panels in all on three walls. The forth wall is home to the fireplace, which I like to convince myself is a diffusor. The panels significantly reduce, but don't eliminate the flutter echo problem in my room. I don't even bother worrying about standing waves or eq, since I don't really have one clearly defined listening position.