if you have a lot of money that is. you can stay in a shared dorm-type room, a private room, or a home-stay depending how much you want to spend, and take conversational Japanese lessons and learn/participate in cultural activities. classes are semi-private (2-3 students each)
keep in mind the prices are just for the accommodations and classes, doesn't include airfare and spending money, and i think only home-stay includes meals by the look of it.
might be a really awesome opportunity for someone who can afford it though
http://midream.jimdo.com/