The Aether Sea is a sci-fantasy game that immediately brings back memories of old-school Spelljammer; classic fantasy races fly magical airships through the void. It's swashbuckling fun that doesn't have a lot of depth, but could definitely be built into a fun campaign with a lot of effort from the GM.
Where this product does shine is the airship combat system; the rules could easily be hacked apart and rebuilt into something for hard sci-fi, or a FATE take on Fantasy Flight Game's "Rogue Trader." Worth a look.
[3 of 5 Stars!]