The bugs grow them big - today we see the Nephilim's ships of the line. The first image is Syd Mead's original 'alien capital ship' sketch - the rest are sketches and renderings done by the team at Origin. Note the file names as well, which frequently refer to the original monikers given these ships. For instance, the Barracuda is the "Skate", the Hydra is the "Marlin", the Kraken is the "Narwhal" and the Tiamat is the "Tsunami". Be careful with that last image (rendered for a magazine advertisement), too - it's a huge file!
Thanks to Captain Johnny for both archiving and providing this material!