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         </blockquote>
         Which was just too cool a piece of trivia to omit.
       </dd>
+
+      <dt><a href="http://cctbx.sourceforge.net"
+         ><b>cctbx - Computational Crystallography Toolbox</b></a></dt>
+      <dd>
+        Computational Crystallography is concerned with the derivation
+        of atomic models of crystal structures, given experimental
+        X-ray diffraction data. The cctbx is an open-source library of
+        fundamental algorithms for crystallographic computations. The
+        core algorithms are implemented in C++ and accessed through
+        higher-level Python interfaces. The cctbx grew together
+        with Boost.Python and is designed from the ground up as
+        a hybrid Python/C++ system. With one minor exception,
+        run-time polymorphism is completely handled by Python. C++
+        compile-time polymorphism is used to implement performance
+        critical algorithms. The Python and C++ layers are seamlessly
+        integrated using Boost.Python.
+
+        The SourceForge cctbx project is organized in modules to
+        facilitate use in non-crystallographic applications.
+        The scitbx module implements a general purpose
+        array family for scientific applications and pure C++
+        ports of FFTPACK and the LBFGS conjugate gradient
+        minimizer.
+      </dd>
     </dl>
     <hr>