(FORTUNE Magazine) – Have you read any good e-books lately? For years bookworms have been tantalized by the promise of electronic book readers that are easy to use yet are able to change their contents at the touch of a button. A really usable e-reading device, however, is long overdue.

At last, a truly exciting new chapter in electronic books has begun. Unfortunately it has begun only in Japan, in kanji and katakana. It has some annoying quirks, and it costs about 40,000 yen, or roughly $375. But it's exciting anyway because it is the first electronic book reader to use a new "electronic paper" technology that's nearly as effortless to carry and read as a paperback, and the product is bound to be released over here soon.

Sony's new Librie EBR-100EP is about the same size and weight as a slim paperback. The black-and-white screen is relatively large, about six inches diagonally, yet the reader itself is so small and light that one can read it one-handed. With ten megabytes of internal storage, it can hold a summer or semester's worth of reading--15 to 20 average-sized novels or a year of FORTUNE--and with an optional Memory Stick card it can match the capacity of your home library. Titles can be downloaded from a store on the Internet to your PC and then transferred to the reader via a cable.

There are a couple of problems, which I'll get to in a bit, but just as you can't judge a book by its cover, the real brilliance of the Librie lies within its pages, er, page.

Sony's e-reader is the first consumer device to use a screen technology developed by E Ink, of Cambridge, Mass., and Philips, the Dutch electronics giant. Unlike earlier e-books that used bulky, battery-draining LCDs, the E Ink--Philips high-resolution screen is thin, energy efficient, and highly readable at any angle. Essentially it's electronic paper, and it's not hard to imagine all sorts of applications for it beyond future e-books. The screen in the Librie is rigid, but rollable and even foldable sheets of E Ink "paper" are already being developed. Imagine having the controls for your iPod or cellphone woven into the sleeve of your jacket, a wristwatch that's almost paper-thin, a map that constantly updates itself, or a desktop-sized display for your wireless PDA that, when it's no longer needed, folds up to fit in a shirt pocket.

Pardon me, I'm hyperventilating.

Technically, the electronic-ink screen is called a microencapsulated electrophoretic display. Millions of tiny capsules, some white, some black, are suspended in a thin layer of liquid. Applying a small electric charge to the white capsules (positive) and black capsules (negative) rearranges them to form readable text that has a higher contrast ratio than even newspaper print. Once the capsules are arranged, they stay in place until signaled to dance once again. That means the screen draws minimal power except for brief moments when "pages" are turned, and thus the book operates for days or weeks on just a quartet of standard AAA batteries. (However, the Librie requires a clumsy, external AC power brick when downloading books from its host PC.) The screen doesn't generate any light of its own and can't be read in the dark, but that's a knock that applies to old-fashioned paper too.

All in all, the device itself is a marvel, but unfortunately it's crippled by an unclever proprietary copyright protection scheme--let's call it "copywrong." (Sony calls it Open MG.) The scheme basically puts the rights of the publisher ahead of the convenience of the user. Only 1,139 titles are available for downloading from the electronic library, mostly books in Japanese, with a few hoary tomes in English like Jules Verne's Journey to the Center of the Earth. Currently there are no newspapers or magazines on the virtual shelves.

And there's another hitch. The Librie has a headphone jack and speakers, which would be nifty for listening to audio books, if only there were some in Sony's format.

Because of the Open MG restrictions, Librie users can't actually store books on the reader. They "rent" books and other content like magazines, comics, and newspapers, which automatically vanish at the end of 60 days. If it's day 61 and you've got one more chapter of an epic novel to finish, the entire book is locked down, and you have to "rent" it again. Open MG is flexible enough to allow publishers to alter the restrictions any way they like, but the current library is strictly use-it-and-lose-it.

The initial library, from a web store called Timebook Town, has a smaller selection than many airport bookstores. Timebook Town allows consumers to rent individual books for prices starting at $2.75. Or, for the monthly yen equivalent of $5.50 to $9.25 a month, they can join a "club" that lets them rent up to five books a month, in categories like literature, new paperbacks, education, business, or, ahem, "sensual."

Why can't they offer a rent-a-book equivalent of Netflix, where you pay a monthly fee and can keep three or more DVD movies as long as you want without any late fees, swapping movies whenever you're ready? That's the kind of e-book that I would gladly support, but on the Librie "storing" anything indefinitely is impossible.

Sony and its publishing partners are being consumer-unfriendly; apparently they believe that all Librie owners are potential thieves. After all, it's not as if the Librie gets magically lighter or easier to carry when expired books go poof.

What's more, the Librie supports only books and documents in its own proprietary format, called BroadBand e-Book, or BBeB. It can't display any of the thousands of e-books already available on public-domain Internet sites like Project Gutenberg. It doesn't support Adobe's Portable Document Format (PDF) or HTML, the ubiquitous coding language used to display web pages. Sony won't even allow it to display simple Microsoft Word .doc or .txt files. Wouldn't it be great to be able to load web pages or office documents on the Librie for reading on the plane? Sorry, not allowed.

Sony must be mortified that it blew the chance to dominate the portable music category in the digital world as it did with the analog Walkman. Instead, Apple's iPod is the new Walkman, in part because it gives users the ability to download, copy, and transfer music easily among devices. There's a lesson there, but one that Sony apparently didn't understand.

The good news is that other e-book readers using the E Ink--Philips technology are expected in coming months, including some with menus and content in English.

And according to E Ink and Philips, the best is yet to come, including new generations of electronic paper that are brighter, larger, and able to redraw pages faster. Within a couple of years they expect to offer color screens. Maybe some company is even designing a book-sized reader that opens to two facing pages, with Wi-Fi connectivity for downloading books and magazines on the run. Maybe publishers will create new electronic magazines embedded with sound, animation, and video clips, or language books that correct your pronunciation.

Now that's a happy ending--or rather, beginning.

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