The three largest ships are Federation ships from the old TSR sci-fi roleplaying game Star Frontiers (more precisely, from the spaceship combat game Knight Hawks):
The big ship is a Federation battleship, and it weighs in at nearly half a pound! I also have a pair of Fed destroyers:
The two small craft come from Citadel Miniatures old spaceships range. The top photo depicts SCP4, the Asimov-Class Escort Cruiser. The bottom pic shows SCP5, the John F . Kennedy-Class Cruiser
Millennium Con in November, Assault on Regulus IV. Hope to see you there.