Proton Pack ergonomic backpack vacuum will have you bustin' dust high and low with its telescoping Neutrona wand. Except for the whole backpack thing, it's more or less what you'd expect a vacuum to be with a couple of attachments, filters, reusable collection bags and even a blower setting. The only big downside is that it's not cordless, so you don't have the freedom a backpack unit would imply.
Well, that, and costing $170. At that price you could buy yourself a pretty sweet vacuum with all the fixin's, if the novelty of having a vacuum as a backpack doesn't sell you.