*[Linux for Palm Tungsten E|http://palmtelinux.sourceforge.net/kernel.shtml]
* [OpenWrt|http://openwrt.org]
* [DD-Wrt|http://www.dd-wrt.com/site/index] to handle WRT routers, WD Netcenter and a host of small NAS and routers.
* [Angstrom Linux|http://www.angstrom-distribution.org]
* [Android] which is Linux-based

For cross-compilation, [OpenEmbedded|http://wiki.openembedded.net/index.php/Main_Page] is a must.