Designed for general purpose computing, embedded controls, machine vision, remote monitoring, and database/web servers, the Debian-based KB9260 measures a wee 3.1 x 3.1 inches and costs only $80 in volume.
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The KB9260 can be bought with two options. The basic option includes the board, a boot loader, a recent Linux kernel (currently 2.6.24), and Buildroot/uClibc installed. This option supports a Busybox-based filesystem, and user-specified amounts of flash and RAM.