Aarn - out of New Zealand, has developed an extreemely innovative way to carry your gear into the back-country.  It is hard to explain this new take on backpacks, but it is certainly worth a look.  They make loads seem a lot lighter than they actually are, and much of your gear is accessible while you hike or climb.  Sam discovered them on a trip to NZ, and we then raced Primal Quest Utah in these packs, used them for both of the 2XtM expeditions, and the recent Rainier expedition.

Aarn is constantly taking feedback and improving the design.  In some ways we feel fortunate that these have not yet made it across the ocean into mainstream America, as they give us a bit of an edge in the ability to do some of the crazy things we do.