(MONEY Magazine) – ''Mega biblion, mega kakon'' (''A big book is a great evil''), said Callimachus, the Greek poet cherished among pedants as the champion of brevity. But what would the Hellenic worthy say about the Wizard? Indeed, what is the Wizard? Aren't we talking books? We are. Take a spelling dictionary with more than 45,000 entries, a thesaurus with 500,000 synonyms, and eight foreign-language phrase books (though not, alas, one in Greek). Throw in a 700-person address book, a calculator, a notebook, an appointment book, an expense report book, calendars for this century and the next, and -- why not? -- an alarm clock that gives the time in 212 cities around the world. Now hold on, Callimachus. It sounds like a big book, but actually all this fits in your shirt pocket. Batteries included. The Wizard, you may have construed already, is not really a book at all, at least in the conventional sense. It's a calculator-size electronic data pack introduced last September that is high-tech's most recent assault on our traditional way of doing things. Sandwiching a tiny keyboard and an eight-line screen into its five-eighths-inch-thick, eight-ounce package, the Wiz -- or the Sharp OZ 7000, as it's more formally known -- is at least as portable as the average paperback. And it is only the leading edge of a number of new books with buttons now threatening to replace the notebook, appointment calendar, Rolodex and a shelf full of reference tomes. Mobility is the prime appeal of these gadgets. Using them is not necessarily easier than using the items they propose to replace. But for anyone whose job sometimes requires being on the move -- salespeople, lawyers, real estate agents, contractors and the like -- an electronic organizer can be handy. As the one with the most bells and whistles, the Wiz is the choice for anyone who hears a subliminal James Bond soundtrack while making business calls. The basic machine costs $250 to $280 (all prices reflect a range from mail-order houses and discounters nationwide), though you'll pay extra for the optional plug-in dictionary/thesaurus ($105) and language translator ($100). For another $130, you can add a communications link that connects your desktop PC to the Wiz and thus escape its infuriatingly small keyboard. Probably the Wizard's main limitation is that the memory available to you for notes, addresses, schedules and such is fairly limited -- only 32K, or about 6% of what's in an average desktop computer. If that's a problem, then you might want to consider its chief competitor, the British-made Psion Organiser II. Introduced in North America in 1987, the Psion Model XP ($200 to $250) is a match for the Wizard in all basic respects and can add up to two optional 128K memory boosters (at $150 each) to swell its total capacity to 288K. Psion also offers a broader range of plug-in software than does the Wizard. Among the possibilities: a finance pack ($50) that duplicates a powerful financial calculator; a data manager ($50) that keeps your files in order; a typing tutor ($50); a pocket spreadsheet ($80) compatible with the industry favorite, Lotus 1-2-3; a phonetic spelling checker ($50); a word processor ($50); and a travel pack ($100) that includes a five-language translator and an expense record. You can connect Psion to your PC (for $120). And you can add a portable printer ($350) that prints on 4 1/4-inch-wide roll paper.

The main weaknesses of the Psion are its relative bulkiness (it's the size of a big electric shaver) and its small, two-line screen. You can overcome at least the first of these limitations by moving to the featherweight of electronic notebooks: the Casio SF-4000. Less powerful, less gadgety and a lot less expensive, the SF-4000 ($99) is alone in attaining a size (five inches by three inches by a half-inch) and weight (4.8 ounces) that will satisfy the digital diarist in the tapered suit. You can store a surprising 750 names and addresses. And its keyboard is laid out in the classic QWERTY typewriter - configuration, rather than in alphabetical order as on the Psion and the Wizard, thus drastically enhancing the speed of entering data. On the down side, the Casio won't connect to your PC, though Casio says it will introduce this month a new and more costly SF-8000 unit that can do so. If you are still not keen on junking your trusty pen-and-ink appointment book but you like the idea of a pushbutton dictionary or thesaurus, you might consider one of the several electronic reference books by Franklin and Selectronics, all of which use the QWERTY keyboard. The Franklin Language Master ($220) includes 80,000 words from a Merriam-Webster dictionary and 487,000 synonyms. Franklin's LM 4000 dictionary/thesaurus ($350) adds a sound chip so that the machine will correctly pronounce the word you are looking for. The Selectronics WordFinder 224, based on the American Heritage Dictionary, costs just $70 but offers 50,000 definitions and more than 220,000 synonyms. And though old Callimachus uttered his famous aphorism some 200 years before the birth of Christ, he probably would appreciate another Selectronics entry due this fall. The EB 2000 ($170) will be a fully digitized Bible sweated down to calculator size, so you can read of your transgressions on the road and perhaps fax in your contrition. Fax vobiscum.