Operating Systems
Linux
Tux.svg
FreeBSD
FreeBSD-logo.png
OpenBSD
OpenBSD logo with Puffy, the pufferfish.
OpenSolaris
OpenSolaris Logo.svg
NetBSD
The NetBSD flag
Darwin
File:Hexley.png
MINIX[MINIX 3 right logo]
Android
Android logo.svg
Security & Privacy
Thunderbird (e-mail and news client)
File:Mozilla Thunderbird logo.png
Winpooch (Anti-spyware)
http://1.bp.blogspot.com/_nhupnqfz6xI/R26DS9Dhc0I/AAAAAAAAAT0/wJ4bvotxca4/s320/screenshot.jpg
ClamWin (antivirus software)
File:ClamWin Logo.png
Wireshark (packet analyzer)
File:Wsicon.svg
ClamAV (antivirus software)
File:Clam.png
SmoothWall (Firewall)
http://www.ssg19.com/wp-content/uploads/2009/07/smoothwall_final-logo1.jpg
Firestarter (Firewall)
http://logofury.com/wp-content/uploads/2005/FIRESTARTER.png
GnuPG (cryptographic software)
File:Gnupg logo.svg
FreeOTFE (Disk Encryption)
FreeOTFE
Database
MySQL
http://wiki.realxtend.org/images/2/2f/Logo-mysql.jpg
PostgreSQL
PostgreSQL
Firebird
http://www.ibexpert.net/ibe/uploads/Main/FirebirdPhoenix_Logo.gif
GNU SQL Server
http://img.epinions.com/images/opti/8a/70/enswDatabasesAllGNU_SQL-resized200.jpg
Orange
http://www.ailab.si/orange/orange-logo-w.png
RapidMiner
http://www.iterating.com/images/wiki_images/d_iterating/rapidminer_logo.JPG
Development
StarUML
http://upload.wikimedia.org/wikipedia/en/thumb/7/71/StarUML_logo.png/250px-StarUML_logo.png
Eclipse
http://www.vivosystems.co.uk/vivo/images/tech/eclipse.jpg
ArgoUML
http://media.nozicaa.com/images/f/fc/Argouml_logo.gif
Bluefish
Bluefish
Aptana
File:Aptana.png
GCC
GCC
Anjuta
Anjuta
Kexi
http://3.bp.blogspot.com/_TNVlo8-kzOA/SH4k5jMQuWI/AAAAAAAAAC4/EPfp8BVtKPk/s320/Kexi_logo.svg