Google's nGram Viewer is an amazing tool that lets users search word frequencies over the history of publishing.

The folks at Zerohedge turned us onto the cool widget after tweeting about a bizarre spike in the early 1940s for "iphone" (some digging reveals this was caused by a surge in sales for the Edison Company's Ediphone dictation device).

The tool searches Google's collection of 5 million digitized books (about 500 billion words) and calculates how many times a word appears in any given year.

While results after 2000 go a little haywire due to changes in data quality, it's still a pretty neat toy to play with.