An as-of-yet undisclosed ship will be going live in the game's cash shop tomorrow, but that's not the really free part. From August 29th to September 1st, around 1:00 p.m. EDT, a new promotional item will be flagged in the store as free. These items are all account-wide unlocks so long as an eligible character is available to claim the item. Who wouldn't like some free stuff for the end of summer?
[Update: The team has also today released more information about upgrading tier 5 ships.]