Obviously we don't have any ex-missile silos to convert into a SiloHome or the like, which would be most awesome; secure, rugged, self contained to a large extent and usually significantly removed from built up areas. Perhaps still listed as a strike-site, so that's a drawback...
Then there is the thought about what kind of every-day structures would actually provide protection from a radiological/nuclear attack as postulated on Gizmodo in their Where to hide in case of nuclear attack article, which is the kind of thing I am always interested in reading. I can't think of a single house I've lived in, or visited that has a cellar in Australia. They just don't do that here, which is silly, considering the heat in summer ...
Then there is the concept of living inside the box which I've been keen on for decades, having seen shipping containers being both discarded and re-purposed. I think it would be most excellent to build a home from these. Research has suggested however that they don't bury well. Which leads me to think of a complex castle like arrangement of many stacked and interconnected units. There are even online resources for floorplan suggestions.
Dreams and hand-waving plans only, at this stage. I'm a long way off being able to do anything like this, but its a fun mental exercise.