Is There A Free Alternative to Lightroom and Aperture?

I respect the technical information presented by Chris Prillo in his many articles and videos. (I may have connected with him a few years ago on Empire Avenue). At any rate, this Chris Prillo video describes how the free/Open source software Blue Marine, replaces the Lightroom and Aperture programs. Programs such as Lightroom and Aperture allow you to straighten, crop, make exposure adjustments and enhance your jpeg images. For those looking for low-cost/no cost programs for processing jpeg images of their art, Blue Marine may be the solution. Let’s face it–some people can’t afford to buy expensive programs. Think about artists in countries where the US Dollar exchange rate is high in relation to their national currency.
In the video, Chris Prillo describes the similarities with the free Blue Marine photo management program and Lightroom and Aperture.
Here are some links to download Blue Marine (there are many other sources– Google *Blue Marine photo* to find them)–
You’ll find a free downloaded of Blue Marine for MAC  available here = http://sourceforge.net/projects/bluemarine/files/latest/download
Older MACs may be able to install Blue Marine, but Apple blocked my installation of this software with this notification:
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