Baccano!

[Zati]

The official site looks nice, and from the description it sounds very interesting too, will probably have to look out for this.

TIAF07 Trailer

A.D. 1711 - Crossing the Atlantic Ocean, alchemists left their home countries heading for a new world. They obtained the “Immortal Drink” from a devil. Those who drank it became immortal, and can only be destroyed by being absorbed into another immortal's right hand.

1930s, New York - People living in the shadowy side of society, a boy named Filo and his boss, the Miser of Martillo Family, a stupid thieving couple, Isaac and Millia, the three Gandol mafia brothers, a delinquent boy named Dallas and his sister Eve, the 200 year old alchemist Cerrad and his assistant Ennis, lived unrelated lives until Cerrad rediscovers the “Immortal Drink”, and their fates become intertwined.

Aboard the Flying Pussy Foot, a transcontinental train from Chicago to New York, there are many kinds of people. For example, Goose and Sharne of the terrorist group “Remlace”, street gangs led by Jacuzzi and Nice, a murderer, Ladd, and his fiancée Lua, Senator Beriam and his daughter Mary, a delinquent boy, a conductor, an informer, etc. There are not only humans on the train, however… The legendary “Rail Tracer”, a ghost who removes passengers from the back cars, also appears.
(From AnimeNfo)

Links :
AniDB
AnimeNfo
ANN
Official Site