This feature, found on the main page of the Yahoo! Japan site is great for finding out route and time information. It was recommended to me by my Japanese businessman friend. He claims it is the most reliable and comprehensive site for this type of functionality. Basically, you just enter the starting and ending stations and then select from options, including: departure date, departure time, arrival time, last train, or none (default). Be warned that the site is Japanese only, but thanks to a good friend such as rikaichan you won’t have too much trouble using it. Highly recommended!