I find this an interesting experiment, as I am often struck by how much history seems to get forgotten. Plan 9 is pretty ripe for picking out lots of cool little things for integration into modern systems, but a lot of it doesn't seem to have resonated out into the world at large. It's unfortunate that Plan 9 wasn't Open Source from the beginning, as it might have been common enough to have inspired more stealing of ideas for other systems.

As it is, we've got a lot of reinvention of ideas happening, often without much forward movement.