Their capabilities should be built into the operating system, something both Microsoft and Apple are working on. Windows users have a while to wait -- Win XP's successor, nicknamed Longhorn, won't ship before the summer of 2006 -- but Apple's Mac OS X Tiger should arrive this spring. Rob Pegoraro writes an interesting article on : Seeking a More Intuitive Search Tool

The file-search tool in is a dog, and not just metaphorically -- a little animated puppy appears on screen to indicate your query's status by wagging its tail, panting, scratching itself and other actions.

If only programmers had put such effort into the rest of this software! Its searches run painfully slowly and routinely yield masses of unrelated files.

A gaggle of contenders has recently put forth replacements for Microsoft's search. Some are popular Web portals -- Ask Jeeves, Google and Yahoo. Some are small, obscure developers -- Copernic and Blinkx. One's a division of Microsoft itself, its MSN Internet service. All six of their search add-ons are free downloads: Ask Jeeves Desktop Search (sp.ask.com/docs/desktop/), Blinkx v2.0 (www.blinkx.com), Copernic Desktop Search 1.2 (www.copernic.com; a version of this should be offered by America Online soon), Google Desktop (desktop.google.com), MSN Toolbar Suite Beta (desktop.msn.com) and Yahoo Desktop Search (desktop.yahoo.com). All require Windows 2000 or XP (save Copernic, which allows Win 98 or newer), and all but Google Desktop and Copernic are in test form -- though none crashed in a week of use.

Every program here can track Word, Excel and PowerPoint documents, audio and image files and Microsoft Outlook e-mail; all but Ask can index PDF files and Outlook Express mail. But if you use a non-Microsoft mail program, only Blinkx and Google welcome you: The former works with Eudora, the latter with Netscape, Mozilla and Thunderbird.

Web-history searching is absent from and Yahoo and half-absent from Ask (it supports only Microsoft's aging Internet Explorer). , and work with the far superior Mozilla Firefox as well. and Google also index chats carried out in, respectively, the Yahoo and AIM instant-messaging programs. Lastly, Copernic and Yahoo can find contacts stored in such software as Outlook and Outlook Express.

Ask, Blinkx, Copernic and Yahoo use their own software. Yahoo's overgrown interface assumes you'll turn a file search into a "CSI" episode. Blinkx's how-cool-am-I looks bury menus and make it easy to miss such crafty features as "Smart Folders" that automatically group files matching search criteria. All these programs let you preview documents, messages and other items without opening them in their original programs. You can even click a link to reply to or forward an e-mail message in your regular mail program.