Approach and Planning tools
Libreoffice: http://www.libreoffice.org
Planner: http://live.gnome.org/Planner
En Debian, Thunderbird se llama Icedove: http://es.wikipedia.org/wiki/Icedove
Hamster: https://github.com/projecthamster
Hamster is a great tool for freelancers, as it allows you to keep track of all the time spent on the job. With the data collected we will be able to elaborate statistics and reports that will be useful to us to invoice and control the projects.
Graphics tools
Pencil: http://pencil.evolus.vn/
Inkscape: https://launchpad.net/typecatcher
Inkscape: http://www.inkscape.org
Gimp: http://www.gimp.org
Photo Collage: https://github.com/adrienverge/PhotoCollage
ImageMagick: http://www.imagemagick.org/
Geeqie: http://www.geeqie.org/
Code editing tools
FileZilla: http://filezilla-project.org
Testing
http://www.apachefriends.org/es/xampp.html
Virtualbox: http://www.virtualbox.org/
Wapiti: http://wapiti.sourceforge.net//
Documentation and office works
Libreoffice: http://www.libreoffice.org
Sinadura: http://www.sinadura.net/es/
So, It's possible !!!
Thank you!
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