Thanks! I haven't thought about drone performances. In retrospect, it's a good starting point. I've seen plenty of videos of drone swarms being synced up to produce shapes and animations.

> Maybe one day in the distant future (if we haven't annihilated each other first) we'll have the technology to built smart grains of sand. But it's seems pointless theorising about something that might just as easily be deprecated by some other fantasy device by our current technological capabilities.

Maybe. But I feel this isn't pointless - I find myself constantly returning to this topic whenever I follow seemingly unrelated avenues of idle curiosity (e.g. "how to build self-maintaining systems", "how to do in-orbit construction" , "how to get rid of household cleaning chores", "how to build a food replicator", "ooh isn't biotech kind of fun", etc.). I think we'll eventually start building "smart matter" at some scale. Might be nanometer. Might be millimeter. Might be meter. Each of those scales has its own physics regime, but I think the concepts behind self-organization will be common. And we're already working on those ideas when studying biology at molecular and cellular level.

> When I've looked this stuff up in the past I've found most of the time it was proprietary.

Do you remember any names? Might be that some of the research is released. Or maybe my employer has access.

> However I have seen papers doing similar work (in the sense that there is transferable logic) in a two dimensional fields, eg matrix reordering.

Thanks, I'll look it up.