I am not as extreme as some of the folks here about weight--and I am a real cheapskate! But I bought a couple of Eureka 3900 packs at Walmart--seems like they were about $50 apiece. They carry enough for us to be out for a week. And we backpack in Yosemite, which means we have to use a bear vault.

But we do have very small sleeping bags, a great MSR pocket Rocket stove. Those are cheap and light. And we don't pack a lot of clothes. I would say that most people pack too many clothes. WE just expect to get dirty, and we bring stuff that can be washed easily and dried quickly.

For five days my pack will weigh about 30-35 pounds, and my wife's will be about 8-10 less than that.