I have seen that book before and was either going to grab it or did and it's sitting in my pile of unread books back in Canada.

I have mine in the back of my wrist about an inch up my arm from where my wrist bends back. It is out of the way of everything. I rarely remember it is there until I go to scratch my wrist.

Of course the downside is that I have to twist my wrist around in a slightly awkward fashion to get it to register.