My reasons about why I find Japan (and Asian culture) so fascinating:
1) Exotic culture: I enjoy learning about cultures different than mine, specially when their philosophies, values, aesthetics, politics, economical system, etc... differ completely from the culture I live on (European / American culutre). I also enjoy learning ancient history (modern history is very interesting too, but it's not as appealing to me as ancient cultures). Japan is one of the most ancient civilitzations of the world, along with China and India. That's why I enjoy it so much, as well as old central and south American civilitzations, Egypt, Greece, Babylon, and ancient cultures in Africa.
2) Philosophy: Western religions (Judaism, Christianism, Islam) tend to focus on behavior codes dictated by a superior and all-mighty deity and the submission of men to this deity's will; and all derivated western ways of thinking derivate from those principles (even illustration and current scientific research are strongly influenced by those religions). Eastern religions tend to focus on the relationship of men with themselves and with the cosmos around them, and are usually based on non-dogmatic assumptions to some degree. Although I consider myself agnostic, learning about religions like Buddhism and Taoism made me think about certain issues and actually gave me one or two answers to some of my "important" questions. (NOTE: I'm not trying to say that these religions are "better" or "truer" than western religions; I'm not talking about faith, I'm talking about ways of approaching certain issues like death or relationship as a society that I did not find satisfying in western religions).
3) Videogames: I discovered videogames when I was 4 and have been in love with them ever since. They're one of the best ways of entertainment that I know, and their versatility is limitless: you can make a game just for playing (like "tetris"), you can make a plane simulator, or you can make a story that actually surrounds the spectator and allows him to interact with the story and participate on it: such degree of interactivity is impossible on any other medium. That's why I've decided to become a videogame programmer. And, like everyone knows, the best games are made in Japan.
4) Manga, Anime, and other forms of story-telling: most of prejudices that exist in both Europe and America do not exist at all in Japan or other Eastern countries. Movies like Battle Royale, Shaolin Soccer, Spirited Away , Crouching Tiger Hidden Dragon, or Ghost In The Shell, although being totally different one from another, all of them share the fact that they move around themes that would hardly be touched in the Western hemisphere, because they would seem either too complex for the spectator, too dumb or too strange. Of course, there's some really good movies made here, but my point is that their way of approaching things is very different from ours, and sometimes much better.
5) Aesthetics: I really like Japanese aesthetics: architecture, painting, ikebana (flower arrangement), and pretty much everything Japanese has a simplicity and elegance that is hardly matched. Straight lines and plain designs, without any kind of unnecessary stuffing, makes it very appealing for me.
6) Usagi Yojimbo: Usagi rocks. Stories like UY make you become interested in the culture that the story takes place on, because of their accurate research and autenticity. All characters are very charismatic, and you soon begin to appreciate their values and moral codes, and the reasons behind them (bushido is a good example). Usagi is also the reason why I have started to practice kendo. And I love it!
Well, that's my two cents.
P.S.: Did you notice? I didn't use a single smiley! I'm learning to moderate myself!

. Well, perhaps not...
P.S.S.: Tounian:: I thought that the most amazing story ever written was the tale of Luthien and Beren from the Silmarillion by Tolkien

. I haven't heard of the 3 kingdoms, I promise to check it out though.