Agreed, Tapioca; Ngram Viewer is an excellent resource which I �ve been trying to work with in the classroom for some years now � I like to use it along with other corpora when, for example, I �m looking for patterns (collocations etc) in authentic texts. For those who �re interested, you can find more detailed information here:

 

 

I �ve found that some of the more advanced features such as wildcard searching, part-of-speech tagging and Ngram Compositions are also useful for answering queries on usage and change in language-related forums. Whether anyone takes any notice of it is another matter.