Gemini
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The Gemini is an FTL-capable freighter in the Fleet which Sharon "Boomer" Valerii escorts to Laura Roslin's convoy of stranded ships during the Cylon attack.
Upon its arrival, Valerii and the Gemini are greeted with the words, "Welcome back, Boomer. Got a lot of thirsty ships here eager to make your friend's acquaintance." From this, one might be lead to believe that the Gemini was transporting water or fuel (Miniseries).
The Gemini also appears in the Original Series as the ship where Cassiopeia is rescued in "Saga of a Star World".