Eating:

• Why not try a teishoku set lunch? Many restaurants offer these, particularly in business districts. Prices usually around ¥ 1,000.
• A tasty bowl of donburi from a kiosk will normally cost ¥ 600 - ¥ 1,000.
• Tachigui-soba (kiosk where you eat standing a bowl of soba noodles) and gyu-don (beef bowl) kiosks, especially around railway stations, should only cost around ¥ 350.

Staying:

• Minshuku are similar to bed and breakfast accommodation, with prices around ¥ 6,000 - 8,500 per night including dinner and breakfast.
  As most minshuku are a family home run as a guesthouse on the side, the service privded is not the same as at a hotel or ryokan. You will often have to put out your own bedding and tidy it away in the morning, respect any curfew your host advises, and fit in with the domestic routine. But the personal service and kindness of your hosts will make it a rewarding stay.
• There are around 360 youth hostels in Japan, costing around ¥ 3,000 per night without meals for Youth Hostel Association members (extra ¥ 1,000 for non-members). The usual youth hostel ethos applies (guests are expected to make their own beds, help with setting tables etc.)

Travelling:

• If you're planning to travel extensively round Japan, make sure you buy an Exchange Order for a Japan Rail Pass before you go. They are available as nation-wide or regional passes, for various durations, and offer substantial savings on the normal rail fares. Suitable if you're going to be entering Japan as a bona-fide tourist with "temporary visitor" status stamped in your passport. Check details and prices.
• Japan has a network of intercity bus services, with ticket prices cheaper than the railways. Recommended by another expert.
• Why not hire a bicycle? It's a great way to see cities like Kyoto. Prices can start from around ¥ 500 per day (higher at weekends & holidays). A deposit is needed, and some places require you to leave your passport too, as security.

General:

• Have fun at a ¥ 500 shop. You'll be surprised what you can find.
• Acccept all those giveaways offered in the street. Usually they're tissues with promotional logos on, advertising a local shop or service. As Japanese toilets aren't usually stocked with paper, those tissues will always come in handy...