I think the Green car on the bullet train is not that special, but there are some trains that have a special first class service- it's called Gran Class. The seats are amazing and even better than domestic first class on many airlines. You also have a choice between a (free) Japanese style or Western style meal and free alcoholic drinks, including red/white wine and Sake!

check it out:

http://www.youtube.com/watch?v=ZqjM03jtl_o

They even have a cute cabin crew member on board and a cabin crew call button in your seat!