When 3M marketers studied office computing habits recently, they determined that although 63% of users worked with confidential information, 67% had monitors that were open to view by passersby. Therefore, their operators tended to come in early or stay late to process confidential work.

Voila! 3M came out with a PC version of the viewing-angle-reducing shield its engineers had developed for automated-teller machines. The apparatus is hung atop a monitor screen and, like a vertical Venetian blind, prevents peeking from either side. Called the Privacy Filter, the product comes in either a 13-inch or a 15-inch diagonal, for about $100.

Unfortunately, there's no version that snugs up to a laptop so a businessperson on an airplane can massage a spreadsheet without fellow passengers tuning in. But if the company gets enough requests, it's likely to market one, since the technology is equally effective with LCD screens. Until then, in-flight keyboarders can fashion a kludge, using tape -- Scotch Tape, of course. -- Robert A. Mamis

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