  The article presents a series of numerical simulations of exact solutions of
the Einstein equations performed using the Cactus code, a complete
3-dimensional machinery for numerical relativity. We describe an application
(``thorn'') for the Cactus code that can be used for evolving a variety of
exact solutions, with and without matter, including solutions used in modern
cosmology for modeling the early stages of the universe. Our main purpose has
been to test the Cactus code on these well-known examples, focusing mainly on
the stability and convergence of the code.
