Weighted nested set

Are there any gems or plugins tha开发者_如何学编程t offer a nested set but with a weight also.

I want to be able to create a nested set and order each subset by its weight.

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Ancestry on git hub looks good

http://github.com/stefankroes/ancestry

node.subtree.all(:order => :weight)

Has anyone done anything similar? I am interested to hear your solutions.