Getting Real book is now free PDF
The 'enter your e-mail address to get X' approach is spreading! Unsurprising.. because it works like gangbusters :-)<p>In this case, you get an e-mail that says: <i>"Periodically we'll drop you a line if we have something interesting to share."</i> (There's also an unsubscribe link.) They'll get to build up an incredible list with this.<p>I'm happy to see 37signals using this approach as it helps legitimize the technique of building a list using free content without disclosing a subscription up front. Till now I've avoided this technique but I imagine it could convert like crazy and build a good list if done right.