What type of Camera and Lens can take photos at this distance?

When that paparazzi photographer took them holiday shots of Kate Middleton topless on holiday at the Chateau d'Autet, what camera can take photos THAT far away.

Here is an image that shows this distance were talking about and it's an incredible distance for such clear photos:

I would love to own a camera that is this powerful but I didn't think they existed until I recently read this story. I imagine they will be expensive but I would be very grateful if someone could source me a lens that could do this. I own a Nikon D300S SLR.

См. статью: What type of Camera and Lens can take photos at this distance?