Shankman has only recently begun to accept sponsor ads in the emails, and doesn't charge the users. How does he grow the list? Classic word-of-mouth marketing merged with social media. Here's a sample of what he does:
- posts frequent updates on his travels on Twitter;
- uses Twitter and the email to alert readers to which cities he's in, to encourage face-to-face meetups;
- asks users to organize HARO happy hours in other locations he's visiting (announced on the list, of course);
- keeps up the Facebook presence and the now-current-home, the HARO website;
- asks happy users to use Digg, Twitter, their own blogs and more to encourage new users to sign up; and
- asks his user community for their ideas on promoting HARO--it's in everyone's interest to do so--and offers prizes. A recent winner had all of us posting the same short signup message on all of our update sites, from LinkedIn and Facebook to Twitter.