Slots is one of the many minigames on your GamePig™ in System Shock 2.
This one, however, is unplayable, and can be only shown modifying game files.
While soldier can play Slots machines on Operations and Recreation Decks, it is not possible in the GamePig™. Looks like VMU doesn't approve of gambling ; )
This game was planned in the development stages along with 5 others that didn't make it into the final product, however its code wasn't finished and as such, its cartridge can't be summoned and the game can't be played.