In the latest CSC magazine there was also this specific column by one of the editors. It appears he, Martin Buckley, once was a 400 and a 412 owner. According to this writing he sold the latter to Jay Kay, so we can add another celeb to the list of famous owners for what it's worth.
For those interested, this is the personal website of Martin Buckley:
The following forum thread does mention a little more about the Fiat 130 Coupe and the 400. Although the heading is referring to Chris Evan's (who apparently owns a 412) there is some linkage to Martin as well. Thought it was a entertaining read to share: