Saw this on Mental Floss and Digg about keyboards from the 60s, 70s, 80s, that were known for signature sounds. The Mellotron, the Hammond Organ, The Minimoog, The Synclaviar, ands the Fender Rhodes. In the blog there are links to excerpts from songs that made these instrument famous (e.g. Strawberry Fields using the Mellotron, etc).
Here is the link: http://www.mentalfloss.com/blogs/archives/17138
I wonder what instruments today will be written about in the future.