Cade said:
Threads
Threads is great, if you enjoyed it also check out The Day After (US nuked instead of UK) and Fail-Safe (second only to The Hunt for Red October in suspension, no happy ending). And why not WarGames, although the style is very different.

I watched The Bay last week. A mockumentary about a new kind of "disease" hitting a town. Not a film I'd recommend but it does have that haunting feeling for fans of disaster "documentaries".