Here's a cool reference site of open-source software alternatives to commercial software.
from http://tech.cybernetnews.com/
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Welcome to osalt.com open source alternative - your quick guide to the best open source software.
Open vs. closed
Find open source alternatives to your favourite commercial products. Browse through our software categories and compare pros and cons of both commercial products as well as open source software.
Why open source
By choosing an open source product, the user obtains a number of advantages compared to commercial products. Besides the fact that open source is always available for free, it is a transparent application, in that you are invited exclusively behind the scenes to view all source code and thereby to suggest improvements to the product. Furthermore, every product is covered by a large dedicated network, or community, who is more than willing to answer any questions, you may have.
from http://tech.cybernetnews.com/
