To make a living in the arts.
That's not some spacy hippy artist talking there, it's Kevin Kelly, editor of "Wired" Magazine and author of an amazing book called "The Long Tail".
That book created a big stir around SEO and other promo/marketing circles when it came out. Simplified, it's about the diminishing ends of the bell curve, and the importance of smaller-return response to marketing.
But he makes a pretty good case for the idea that if you have as few as 1000 people out there who talk you up and buy your latest ebook or mp3 or album or whatever, you can get by on it.
This link is to Kelly's site, explaining this concept. Even without the math and boogie-woogie, it's a heavy concept. You don't really need 40,000 people visiting your blog...just 1000 people in the whole world who dig your work enough to support it...and therefore you.1000 True Fans