There's an interesting trend in Japan in the way people speak, that I noticed particularly when I was back there. Younger people in particular seem to be very reluctant to use the word "I" to refer to themselves.
The Japanese word for "I" varies depending on who is saying it to whom, but the most commonly used words are 私 （わたし watashi) and 僕 (ぼく boku). Watashi is used by women (and girls) and men (the very polite way to say the same word/kanji is watakushi) and boku is used mostly by men and boys.
Another word that can be used to point to onnesself is 自分 (じぶん jibun). If you translated jibun though, it would be closer to 'myself' or 'oneself' rather than I - in other words, it's more passive and third-personish than watashi or boku, which clearly do mean I.
Here's an example sentence using both watashi and jibun.
私はラーメンが好きです。 (watashi wa ramen ga suki desu.)
自分はラーメンが好きです。 (jibun wa ramen ga suki desu.)
Both mean "I like ramen", but the second sentence is more like "Myself likes ramen".
自分 has always been in regular use to mean oneself. However, recently many people use a turn of phrase that is even more passive, when expressing their opinions - 自分の中 (じぶんのなか jibun no naka), which means 'within myself'.
In March, there were several news reports in the Japanese media about the difficulties soon-to-be college graduates are having getting 内定 (ないてい naitei), or internal pre-approval for a job (the step usually taken by Japanese companies prior to officially hiring someone) this year due to the bad economy. Young people were being encouraged by employment agencies and others to look at small and midsize companies and not just the large corporations, but one young girl expressed this sentiment, which is probably shared by many of her colleagues:
自分の中では大手企業を希望してます。(じぶんのなかではおおてきぎょうをきぼうしてます jibun no naka de wa ohtekigyou o kibou shitemasu.)
A rough translation of this would be "I want to go to a large corporation" but a nuanced one would be "Within myself, there is a wish for a large corporation". Note the difference in tone - it's really quite passive...one could even say, depending on the tone, passive-aggressive.
I never noticed people using 自分の中 so much say, 10-15 years ago. It must say something about the way people in their 20-30s and younger think these days. (Older people still use watashi, boku etc.)
A boom within myself?
Combining 自分の中 with a typical example of an English word that's incorporated into Japanese and takes on a different meaning from the original, is the phrase
自分の中でブーム （じぶんのなかでぶーむ jibun no naka de buumu)
Directly translated it comes out to 'a boom within myself'. No, that doesn't mean that someone swallowed a bomb that went BOOM, or even that someone had a very spicy burrito and farted...um never mind. ^_^ It uses the meaning of boom as it's defined on this page - "a sudden increase in popularity". So 自分の中でブーム really means that "I am very much into/passonate about/obsessed with (whatever it is)". Example:
最近パンを焼くのが、自分の中でブームです。(saikin pan o yaku noga, jibun no naka de buumu desu.) - Recently, I am very into baking bread.
This use of boom has been turned into it's own new combination wasei-eigo (Japanese-English) word マイブーム (maibuumu), combining "my" and "boom". Many people use that with 自分の中, e.g. 自分の中でマイブーム - a my-boom within myself. A "my-boom" tends to mean a short term obsessive interest in something, that eventually burns out.
I guess you could say that people who are considered to be otaku are always having 自分の中でマイブーム, though it's not limited to those who might be defined as otaku. Though if you look at things a certain way, almost all Japanese people are otaku....