This chart was published in 1880, in a book called Conspectus of the History of Political Parties, by Walter R. Houghton. In July, Susan Schulten put it on her blog, Andrew Sullivan mentioned it on his, and I put it up on Tumblr. Here it is full-size.
This was today’s xkcd comic. Click on it for a zoomable version.
I think the chart from the Houghton book is more elegant, but this one is nice also.
Panther Red 
