High-end software packages from giants like Adobe and Microsoft are an absolute pleasure to use – they’re the industry standard for a reason. But legitimate retail copies of the software can cost a pretty penny and put a dent in the wallets of small businesses and individuals.

However, there are free, open-source alternatives that are widely available on the web that can tackle some of the tasks that the big-brother software packages do on a regular basis. I’ve lined up a number of alternatives to the most popular programs – trust me, they can be very useful in a pinch.

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Adobe Photoshop Alternatives: GIMP and GIMPshop – GIMP, otherwise known as the GNU Image Manipulation Program, is one of the oldest and most well-known open-source projects out there today. The image editing program offers most basic and intermediate level functions, like resizing, editing, cropping, layers, filters, and more. Although you won’t be getting the same level of tools available in its powerful, high-end counterpart, don’t count the GIMP out for image editing needed in a pinch.

GIMPshop is a modification to the GIMP software package that changes the menus and user interface to offer an experience more similar to Photoshop. GIMP is available for Windows, Mac, Linux, and more, while GIMPshop is only available to Windows users.

More Photoshop Alternatives: CinePaint, Krita

Microsoft Office Alternatives: OpenOffice – If you’ve used a computer in the past 20 years, chances are that it had some form of the Microsoft Office suite installed. In recent years, however, OpenOffice, the Sun Microsystem-backed office suite, has been a turning a huge number of heads in the business world and has become a legitimate contender in the office suite arena. Its package offers Writer (Word), Calc (Excel), Impress (PowerPoint), Base (Access), Draw (Visio), and Math (Equation Editor).

You won’t be getting all of the Office Suite knickknacks, like Outlook, Publisher, InfoPath, OneNote, SharePoint, and Groove, but for the core functions, OpenOffice is definitely a solid choice. OpenOffice 3 is available for Windows, Mac, and Linux, and is ready to download today.

More Microsoft Office Alternatives: KOffice, Google Docs

Microsoft Outlook Alternatives: Thunderbird: – Outlook makes the corporate world go round – we all know that. But there are a couple of viable open source alternatives to the email-handling software that are available on multiple platforms. Mozilla, creators of the Firefox web browser, developed a fully-featured, open-source email client named Thunderbird. Thunderbird offers email search, message tagging, a fully customizable interface, add-ons and extensions, and more.

Mozilla Thunderbird 2 is available for Windows, Mac, and Linux and is ready to download today.

More Microsoft Outlook Alternatives: Evolution (for Linux)