My book "Computation at Compile Time" is now available!  The book documents the implementation of libbug (a library for Gambit), 

Advertisement:  http://billsix.github.io/cac.html
Source: https://github.com/billsix/bug
Book site: http://www.lulu.com/shop/bill-six/computation-at-compile-time/hardcover/product-23045340.html

I plan to advertise the site on hacker news/slashdot/etc on Monday morning, so please don't post anything about it until then.

Thanks to all for feedback on the project!

Bill