Have never seen this before.
Although, I am not real hip about gear so maybe it exist?
Its a pack with storage compartment build into the straps and waist belt. Was Thinking it would reduce the main pack size but also redistribute some of the weight. As well as make more common used items more excessable?
While I am on different pack design ideas..oviously center of gravity is the major limitation.. Otherwise, has anyone ever experimented with say a hip or waist pack?