Home made absorption panels.....


I would like to hear some good inexpensive ways to make absorption panels, particularly at first point of reflection.

Thanks.
capt369
oops, I responded too early to these useful suggestions in my previous post. They`ve all been useful and will be concidered. Thanks for your input.
Tvad's suggestion is a good one, because you can tailor the look of the panels to your aesthetics and room decor.
Does the bookcase filled with books thing really work? If so, would it be better than, say Tvad's homemade panels? I have two bookcases full of books that I could use for this purpose but before I was thinking of draping a cloth over them so they'd be less distracting.
Glitch, a couple months ago I took down my wall mounted bookcases so my friend could paint the walls for me while I was at work. I was shocked how much echo there was without them on the walls.