[bdonlan]

Japan has a good solution for this - most of the larger train stations (and many of the medium-sized ones as well) have "coin lockers" (which, despite the name, these days often take transit IC cards instead of coins) you can rent to store your stuff until you're ready to head home. In larger tourist hubs like Akihabara there'll also be a ton of lockers in the vicinity of the station run by third parties as well.