Other than being a free complete office suite, OpenOffice allows users to install extensions to improve its functionality and enhance the user experience. Here is a list of useful extensions for you.

Draw is probably the most under-estimated of the OpenOffice.org applications. Either users seem to expect it to be equivalent to the GIMP or Visio, or they fail to see its desktop publishing possibilities -- but in all cases they are disappointed. Probably, that explains why the OpenOffice.org Extensions page has only a handful of Draw extensions.

Extensions have long been written for OpenOffice.org Writer. However, the fact that attention is finally being paid to other applications seems a sign that OpenOffice.org is finally starting to develop an active extension-writing community.

As with Firefox, you can extend Thunderbird's functionality by installing extensions. Mozilla's official extension repository has quite a few nifty tools on offer, and which ones you choose to install depends entirely on your needs. There are, however, a few extensions that you might find indispensable no matter how you use Thunderbird.

Easy PDF editing is coming to OpenOffice.org, but you'll have to be patient for a few months. Recently posted to the OpenOffice.org Extensions site, the Sun PDF Import extension (SPI) is only in beta, and only works with recent developer builds of OpenOffice.org 3.0, which is scheduled for September release.

So you've written a nifty OpenOffice.org macro and want to share it with the world. You can, of course, publish the code on your Web site, but a better way to go is to pack it as an easy-to-install OpenOffice.org extension.

EuroOffice is the name of a free and open-source OpenOffice.org derivative and a set of accompanying free and non-free extensions. Most of the extensions also work with "vanilla" OpenOffice.org.

Now, a lot of people publish lists of 'best' extensions. It's quick and easy to make these lists. One difference between my list and some of those "99 Must Have, Best Firefox Extensions!" is that is the real list of the extensions that I use every day. These don't just sound good, they work well.

Using extensions like TwitterFox and TwitBin , you can post messages to Twitter directly from within the Firefox browser. But what if you spend most of your time in OpenOffice.org and want to submit tweets without leaving the convenience of the office suite? A simple OpenOffice.org Basic macro can help you to solve this problem.