Gifting as a principle for museum experiences

I was talking to Tom Steinberg the other day, the founder of http://www.mysociety.org/, a community of developers who have made really useful social tools like Pledgebank, Groups Near You etc, oh, and I should mention the brilliant Freedom of Information site that lets you file information requests to government departments. Anyway, Tom made an interesting point that museums could promote themselves as much more about exchange or gifting, rather than a one-way experience where you are allowed in to see the great riches of the nation's heritage. It would be far more compelling, he said, if when we visit a museum (or museum website) we gain something e.g. knowledge or enjoyment but we are also invited to give some small piece of culture or history. I liked this idea, and since then came across the idea of gifting explored in sociological and web 2.0 terms by Nina Simon on Museum 2.0 http://museumtwo.blogspot.com/2008/04/participation-through-gifting-pass-it.html She raises the question about how we can extend gifting to museums and culture online. It would be interesting to gather and share some examples.