Credit crunch making your office system look lean? There's no need to fret when there are perfectly good productivity tools available for free.

Here's our pick of the free productivity-boosting programs every Windows user should own.

1.Thunderbird 2

Based on Mozilla code, what Firefox does for web browsing, Thunderbird does for email. Including advanced features like message tagging, saved searches and Gmail integration, you can use it for POP, IMAP and webmail accounts.

2. OpenOffice.org

Not one productivity tool but a whole suite of them. OpenOffice boasts word processing, drawing, spreadsheet, presentation and database apps in one handy package. Microsoft Office compatibility makes it easy to switch.

3. PrimoPDF

Adobe's Portable Document Format is ideal for delivering content across different platforms. PrimoPDF makes it free to create industry standard PDFs from over 300 file types. Installed as a printer driver, you can output from almost any program.

4. Inkscape

A graphics package that's ideal for creating clipart, charts and posters, Inkscape that will cost you nothing. With vector drawing tools on a par with professional programs, it outputs files in the open source SVG format.

5. Sunbird

Most free email tools are missing the calendar and scheduling features of Microsoft Outlook. Sunbird fills that gap, with a robust, open source application that uses a SQL based storage mechanism for security and strength.

6. NotePad++

The Notepad that comes free with Windows has nothing on this word crunching supertool. With it's tabbed interface, saved workspace states, syntax highlighting, auto-completion and text processing features NotePad++ is ideal for everyday use or even coding.

7. GIMPShop

A longtime Linux favourite, The GIMP (Gnu Image Manipulation Program) sought to emulate the main features of bitmap editing tool Photoshop for free. This remix makes The GIMP's interface look and behave more like Photoshop too.

8. XnView

Windows built in image viewer balks at some formats, but not XnView. It imports around 400 different file types an exports about 50. If that wasn't enough, you can also make simple edits, like cropping and resizing or create slideshows.

9. TurboLister

eBay listings are made easy with TurboLister. Combining design and database tools, the package connects to your eBay account to give you template based control over the auctions you place online.

10. Diagram Designer

Diagram Designer helps you create flow charts, circuit boards and graphs. In other words, it does a similar job to Microsoft Visio, but for free.

11. Trillian

Replace all your instant messaging clients with Trillian. It connects to Yahoo, Windows Live, ICQ, AIM and Internet Relay chat. There's even built in support for sending SMS messages via a gateway.

12. 7-Zip

Windows XP and Vista can open ZIP files, but can't read RAR, LZH, ARJ or any of the other additional formats 7-Zip is familiar with. You can even browse disk images in ISO format.

13. DeBrief 2.3

If you're the kind of person who scribbles on envelopes, bus tickets and any other scrap then DeBrief is for you. This note-taking application helps you organise your lists, ideas and thoughts.

14. AceMoney Lite

Financial management tools are rarely free, so it's gratifying to find one that's so good at its job. Track your spending, pay bills on time, manage debts and household budgets with AceMoney Lite.

15. Jarte

Built on the same engine as Windows WordPad, Jarte adds features that make it into a useful word processor. Spell checking, word count and support for Microsoft DOC formats make it a must.

16. TimeTo

More than just a calendar application or "to-do" list, TimeTo enables you to manage your commitments hour by hour, day by day.

17. Picasa 3

Google's photo sharing and management tool beats most others feature for feature. Picasa 3 lets you quickly import pics direct from your camera, fix them with the built-in filters and organise them in albums.

18. Ashampoo Burning Studio Free 6

Available only at download.com, this is an earlier edition of a commercial program featuring CD, DVD and Blu-ray burning capabilities. Great for music compilations and data back-ups.

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