They're a little old-school (OS-Tan girls are *SO* 2004) but I want to resurrect the concept. The OS-Tan girls were a manga phenomenon a few years back featuring Mac and Windows characters in sometimes raunchy narratives (imagine what an anthropomorphized virus could do to a Windows-Tan...) This is the first instance I've seen of Linux-Tan girls.
By request, the ArchLinux-Tan girl is third in a series of 11 Linux-Tan GDM themes.
Others planned: openSUSE, Gentoo, Fedora Core, Red Hat, Mandriva, Debian, Knoppix, and generic Linux. Let me know if there's one you want bumped to the top of the list.
The original artwork belongs to Juzo-kun (http://www.jkhp.it/) and is released under a Creative Commons license. If you take this package apart for other projects, please credit the original author so she and fine artists like her will continue to share their talents with the rest of us.
The GDM format was borrowed from Ubuntu's Human Circle of Friends by Mark Shuttleworth and company and the badge is by Peter Mathijssen (http://www.gnome-look.org/content/show.php/Stickers+7?content=56776).