If you are on a very tight budget and can't afford the other cheap accommodation options (Love Hotels, Capsule Hotels, sleeping in Internet Cafes and Youth Hostels) or just looking to meet new people then you may want to consider Couch Surfing.
CS is a project where people around the world list themselves as free places to stay for visitors. Through the site you can contact them and see if it's alright for you to visit on specific dates and stay for X amount of time.
There are loads of people in Japan offering this. 1200+ in Tokyo alone.
A few good friends of ours tried CS across Japan. They had mixed things to say. The first guy they stayed with was an American ex-pat who treated them like family. He showed them the sites of Tokyo like it was his job, paid for meals out etc. Sounds great. The second person, however, was so bad that they left almost immediately and stayed the night in an internet cafe instead. Apparently she had a couple of dogs who lived in awful conditions and were kicked around the house. The place stank, too. Well, that's a 50/50 result. Better than the odds at Pachinko. People have usually been rated by other users, so I'd check that first.
I haven't tried it, so I can't give you my opinion, but if you have the guts to stay with a complete stranger then Japan is probably one of the safest places to do so. Incidentally, you can also meet people on the site just for a cup of coffee and tourism advice.
If you do or have tried it, let us know about your experience in the comments box below.
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