So I've just discovered Google News has an Archive Search feature, which lets you search historical news articles for a given phrase and return a histogram of hits. It makes an interesting way to map the rise and fall of concepts, events, and phrases in the public mind. Here are some queries I've come across that have interesting patterns:
First, some normalization: a search for the, and, a, etc gives us an estimate of the number of articles on record-- gradual uphill increases like those seen here should be attributed to the nature of the data set and not the data itself. (Science!)
There's lots of modern words and phrases we can watch grow into popularity, like outer space and DNA. More subtly, we see the emergence of the adjective global starting in the 1940's, and a sudden rise in popularity of the word deadly in the 1980's (wut?). Robot grows gradually in use over the 20th century, though there is a funny spike in the summer of 1944, which correlates to German use of "robotic" planes to bomb Britain during WW2. And atom shows a boom midway through 1945, of course, though it's curious to note that its appearance in the news is deminished prior to that, during the war-- this could be a result of wartime news censorship, but then if you search science itself, you see that science reporting in general tends to drop during wartime, which could also be a factor.
Then some words are tied to a certain time period-- like fallout shelter and elixir. Others fall from popularity: for some odd reason, the word obituary became wildly unpopular in 1986, while the civil rights movement (I assume) soundly quashed use of the word negro after the late 60's. And lipstick, after rising in popularity starting in the roaring 20's (a phrase which didn't actually take off 'til the 60's-- does that mean 20's culture was to the 60's what baby boomer culture is to the 90's/today?), lipstick suffered a temporary blow in the 1970's, either from the growth of the feminist movement or simply from the fashion of the time.
What other trends are out there?