The only way I could imagine (and it isn't hard to imagine) is a state whose main goal is to render itself obsolete by encoraging us to create strong and self sustainable communities and basically only serving as a helpful resource. This could lead to the formation of autonomous zones where people could experiment with whatever kind of ideas they'd like outside of the law that everyone is following in the rest of the country. In those communities, we'd have a chance to see what human nature looks like under a variety of different circumstances.
I would like for us to adopt a gift economy to the greatest extent possible, but I realize we have a long way to go. In my lifetime I hope to see pay-what-you-want become less fringe and more supported by the mainstream.