As of today, more than 41,500 people were following Denis Leary on Twitter @denisleary for free. The calculation is that there are many more people who like Leary enough to pay for a book of his Tweets. Because that book is coming out in hardcover this December. "Suck on This Year." No, that's the book title.
Here is Leary's video trailer to promote the book. Impressed? Jealous? A third thing?