Over the weekend, LibreOffice took the Experiment award for most appreciated software at the Open World Forum in Paris. I use LibreOffice every day, so I definitely think the award is well-deserved. Although I use some extensions, LibreOffice (and OpenOffice) have a collection of add-ons that I haven't even explored yet. Here are three particularly useful add-ons to improve your office tools:

Oracle PDF Extension: This handy extension allows you to open and edit PDF files within LibreOffice or OpenOffice. If there's a better, non-Adobe PDF editor, I haven't found it yet (but feel free to leave comments with your recommendations).

Writer's Tools: If you do much writing, you'll want to check out my former colleague's set of utilities. Dmitri Popov has shared his Writer's Tools to help writers get the most out of LibreOffice and OpenOffice. His Lookup Tool lets you select a word to look up in online resources. Popov also provides several options for backing up your documents. Email Backup allows you to email a backup copy of your document, or you can do a remote backup to an FTP server or Amazon S3. A timer utility allows you to track time spent on a document, which is great if you bill by the hour, for example. Other utilities in his collection include a task management tool, URL shortening tool, and utilities that work with Google tools, such as Google Translate and Google Maps. If you need help with Writer's Tools, you can join the Google group.

Compose Special Characters: If you work with an international team (or you often write about Mötley Crüe), you'll want to install this extension, which allows you to use keystrokes to insert special characters. After downloading and installing this extension, restart LibreOffice or OpenOffice and then you'll see the Compose Character option in the Insert menu. There you can select the character you need or use the keystroke option, which are shown by the character, to insert it.

I'm sure there are extensions I'll love that I just haven't discovered yet. Which ones do you recommend as “must haves”?