Once Upon a Time in War is a photographic retrospect of the Great War, World War II, Korean War, Vietnam and the War on Terror.
Photos from the war. A slideshow of photos taken by German soldier Werner Wiehe... vermisst in Russland, 1944. (While viewing the slideshow, might I suggest playing some appropriate musical accompaniment, arranged in sequential order?!)
Britain's Maunsell Sea Forts [wiki] were built during WWII as part of the coastal defense system. They were decommissioned in the 1950's, but many of them remain in use for non-military purposes (this is arguably the most famous). Some great photos here. [previously on metafilter]
LA6NCA's WW2 German Radio Collection Pictures and a little history on many WW2 German radios including a cute as a button spy radio and the Lichtsprechgerät 80, an incoherent light audio transceiver. Also featured are a few photo essays of the equipment in use (Enigma, Luftwaffe Signals unit redeploying). [dorian
Fantastic photographs taken and developed on the island of Tinian during WW2, now scanned and restored. There are some bodies and nudity/nude art, so it's potentially NSFW.