If you’re looking for a challenging model to build then look no further than the Metal Earth Apollo Lunar Lander ($13). If you don’t know the story, the Lunar Lander was the spacecraft that carried two astronauts from the orbiter to the surface of the moon and back. Six lunar modules landed on the Moon between 1969 and 1972. The model is made from laser cut steel and when fully assembled measures 2″x2″x4″ (lxwxh). If this model is too challenging give the Metal Earth Mars Rover ($11) a shot.