Most everyone who's had some experience with free open source software has learned about the OpenOffice.org suite of productivity programs: a word processor, spreadsheet, presentation, database, and drawing tool that provide a good deal of the functionality of their commercial counterparts. For users who need powerful productivity tools but don't require a high degree of compatibility with Microsoft-formatted files, OpenOffice.org is almost a no-brainer.

But apart from OpenOffice.org, what else is there? I dug into my own program folders and searched the far corners of the Web to come up with a cache of free and open source productivity applications for a range of desktop productivity tasks: word processing, page layout, graphics editing, illustration, task management, and more. Some of these tools are worthy substitutes for expensive commercial counterparts. All of them are available for Windows, and nearly all are available for Linux and Mac OS X as well.

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Free productivity software is hard to get right, which explains why for every one program I included here, three others didn't make the cut. We still have no viable free open source video-editing solution yet, for instance -- although a number of projects, like VideoLAN Movie Creator, are in the works. But the roster of available free programs has grown remarkably in the last few years alone, and new apps of all kinds continue to pop up.

Desktop productivity tool No. 1: AbiWord 2.8.6

If all you want is a simple word processing application, and OpenOffice.org is overkill, consider AbiWord 2.8.6. Written to emulate the look and feel of Microsoft Word circa Office 97 through Office 2003, AbiWord also dependably emulates the vast majority of Word functions. Especially useful is a live-collaboration function that lets you connect to another AbiWord user across a network and work on the same document in real time. A word of caution: AbiWord can be tripped up by documents created in other programs. Some types of formatting aren't properly preserved, and some features supported in Word (and OpenOffice.org) don't always function as expected. When working with files created outside AbiWord, you should use copies instead of the originals.