It's been discussed a few times in the past, and always gets me thinking. Personally, I like the keep-away-caveman scenario: (somehow) engineer a structure to

It's been discussed a few times in the past, and always gets me thinking. Personally, I like the keep-away-caveman scenario: (somehow) engineer a structure to generate low-frequency harmonics for as long as that radioactive material's around. http://en.wikipedia.org/wiki/Infrasound http://en.wikipedia.org/wiki/Infrasound Combine that with the most evil-looking shrubbery/stone structures/whatever you can find. You'll have created a land of ghosts and demons for those future people, assuming the site isn't bingoed by a meteor. Then, when they redevelop society to a point where industrial music is popular again, people can have raves there. They won't even need glow sticks! (Come to think of it, I'd love to do something like that anyway. Sounds like a great landscaping project for a hunting lodge packed full of taxidermy.)