Some of my favorite software/projects on Ubuntu:
Banshee
BleachBit
Boxee
Do
Docky
The elementary Project
Firefox
F-Spot
GIMP
Google Earth
Gwibber
Inkscape
Minitube
Namebench
The R Project for Statistical Computing
Thunderbird
Tomboy
Tracker
Wine
Zeitgeist / 
Gnome Activity Journal / 
Sezen
Board & Card Games
Q&A for people who like playing board games, designing board games or modifying the rules of existing board games
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693 reputation
210
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4 questions
14 answers
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1 questions
11 answers
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413
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2 questions
12 answers
Cross Validated
Q&A for statisticians, data analysts, data miners and data visualization experts
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293 reputation
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4 questions
5 answers
196 reputation
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1 answers
Mathematics
Q&A for people studying math at any level and professionals in related fields
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154 reputation
5
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1 answers
Stack Overflow
Q&A for professional and enthusiast programmers
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15
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TeX - LaTeX
Q&A for users of TeX, LaTeX, ConTeXt, and related typesetting systems
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133 reputation
4
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1 answers
Android Enthusiasts
Q&A for enthusiasts and power users of the Android operating system
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103 reputation
2
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Meta Stack Overflow
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
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101 reputation
1
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Parenting
Q&A for parents, grandparents, nannies and others with a parenting role
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101 reputation
1
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Area 51
Stack Exchange Network staging zone, where users come together to build new Q&A sites
Joined 2 years ago, last seen 1 year ago
101 reputation
1
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