John Hendryx at Monergism.com is making available a free eBook edition of J. Gresham Machen's classic text Christianity and Liberalism.
This is one of those texts all Reformed Christians should read at least once. Here it is, for free. No excuses!
John also has a nice link to my Amillennialism 101 series (which is also found here on the Riddleblog's sidebar)