[Firebird]

i assume you are Australian wich gives you the great possibility to get a 1 year Working Holiday Visa. Your money will keep you travelling around 1 month maybe 1 and a half (as the A$ is quite week) or it will keep you living in one city for 2 months.
You are a english native speaker wich will give you the possibility to get work as a teacher. It will be easier if you have a university degree, but it is possible without (just alot more difficult).
If you can speak Japanese you will easily find another job, wich just doesnt pay well. Other than that you will be very limited.
I have been 1 year in Australia with WHV and im now in Japan since 6 month and i have to say that Japan is alot more difficult.
First to do backpacking.... this country doesnt have the culture and facilities to Backpack like Australia. Youthhostels are quite expensive as is public transport. Most travellers here will either have a big wallet, or just stay for a short time.
Second: finding a job wich can actually keep you alive is not as easy as in Australia as most jobs pay bad and accomodation tends to be expensive.

My advice is: Save up some more money (if possible), learn japanese basics (you will be living there for a year after all) and get a book (there are a few out there wich are something like "WHV Japan" or "live work and play in Japan") to give you a overfiew of you possibilitys.

Overall, i´d say you can do it, but you might end up working most of the year and might have a rough start. If you keep your wallet closed in the beginning till you find a job, than you should be alright.
Its definetly worth it, its a beautifull country with some very nice people and lots to see, so i recommend you to give it a try. Just keep in mind that you will be backpacking Asias most expensive country, you could go longer in China, Vietnam,... or even Korea, but only Korea (besides Japan) will offer you (as Australian) a Working Holiday Visa. Off course Japan will be a special experience and i think you would not have come to the Japanforum if you wanted to go to Korea ; )

Oh, and MMM i dont want to tell you off, because i like that you try to answer every question (and apreciate that), but could you please consider the Working Holiday Visa possibility for other countrys than America when giving answers to this kind of questions? I know that you don´t know alot about this visa, so just write smth like "... but you might be able to get a Working Holiday Visa...."
Sorry and thanks : D