The products on this site seem grossly overpriced. I wonder what is it about breathing that makes these so pricey. I have tons of books on breathing and two books stand out- in fact I believe they will be all you need on breathing- Breathwalking and Tao of breathing. The first book discusses several breathing patterns for alertness, relaxation , concentration etc.
I would highly recommend the book Breathwalking. If you decide to buy something from breathing.com, let us know how they are.
Regards,
blue_sky
