This site, called "I Write Like," allows you to paste a block of text that you've written, which it analyzes and I suppose compares against famous/popular/iconic writers and tells you what writer your writing is most similar to. So I pasted one of my more verbose blog entries in there, and got this result:
I then pasted a page of text from some fictional writing I've done and got the same result. So. I take it with a bucket of salt; I don't write all that well. But that's a pretty huge compliment - Twain is one of my all time favorites. It's a fun little idea for a site.