Living on a budget would seem hard in the most expensive city in the world Businessweek: Most Expensive Cities 2010, one would find it difficult to afford to even eat. Luckily there are shops like Sukiya http://www.sukiya.jp/, Saizeriya http://en.wikipedia.org/wiki/Saizeriya and many small mom & pop shops to eat at for a small amount.
This bowl is a spicy ground meat mix on top of rice and a soft boiled egg comes with a bowl of soup and pickled veggies. This will fill you up and it costs under 500yen. I sat down with a copy of the manga CROWS which I also picked up really cheap for only 105yen from the chain used book store called Book Off http://en.wikipedia.org/wiki/Book_Off.
The manga CROWS is by Hiroshi Takahashi 高橋ヒロシ http://en.wikipedia.org/wiki/Crows_(manga) who created this series in 1990 who has also made a smin off call WORST, both involving stories of high school delinquents gangs. In 2007 a Movie called Crows Zero, the story of the gangs beginnings was released http://en.wikipedia.org/wiki/Crows_ZERO Visually the movies look good, but overall they lack real interest, but i could be wrong, check it out and tell me what you think.
Music video for the Crows soundtrack, The Street Beats - I wanna change