OneTech Tip has addressed alternatives to Windows and Mac OSX but what about the software. There are hundreds if not thousands of software that is free to use without a cost to the user. In some cases the open sourced software is sometime better, more efficient or meets your specific needs in comparison to larger, bloated commercial software.

Open Source Alternative is a great place to start if your looking for some free and open sourced software ranging from office software to games as well. Now, the site I noticed does not have an exhaustive list but it does provide some good suggestions for alternative software. For example, you may search for an alternative to Photoshop and it will yield Gimp.

If you are looking into becoming a more part of the open sourced movement consider this site to help you meet all your needs. Here's a challenge, try only using open source software for a week or a month.

Open Source as Alternative: http://www.osalt.com/