The Linaro Project has a number of linux images. There are a number of SOC development platforms that support Linux.
Canonical's Mark Shuttleworth currently has an Ubuntu phone OS preview, which one can flash to the Google Nexus 7.
Neal Peacock, of Peacock Imports, completed a successful crowd funding campaign on Indiegogo and is selling Chinese commodity ARM-Allwinner A10 tablets (Pengpod 700 and Pengpod 1000) running LXDE (not powerful enough to run Plasma Active well). The Pengpods are made possible in part due to the efforts of the Linux Sunxi Project.
Aaron Seigo, of KDE, on "Luminosity of Free Software" episode 2 recently stated the Vivaldi tablet (Plasma Active) will be released sometime this year and will only use free software hardware drivers. He also welcomed others to sell Vivaldi competitors (free Plasma Acitve ARM tablets).
Maybe a Trisquel Plasma Active ARM tablet in the near future?
