Came across Bifferboard that should consume 1 W here 
http://www.sunspot.co.uk/Projects/Sweex.htm


Ordered it. Bifferboard was delivered with OpenWRT.
On OpenWRT from could not opkg install modules for webcam.
Tried to compile OpenWRT myself, but it did not run.
 

Next tried to install Debian on Bifferboard:
http://www.sunspot.co.uk/Projects/Bifferboard/Debian_distro.html
Distro from Bifferos:
wget http://bifferos.planetlee.eu/bb-bin-1.2.tar.bz2


Bifferos Distro could not compile C code due to version magic changing kernel modules version.
Finally burned Debian version pipe from
http://blog.famzah.net/2009/11/20/running-debian-on-bifferboard/ 

Experience with the latest: 
mjpg-streamer and HD webcam runs OK.
ffmpeg to make video from pictures did not run - no math processor. 
Infinite-loop shell scripts stop working after a few min.
This script was used to monitor motion detector. Solution would be to try interrupts in future. 

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Question to developers:
"I have set up a HD webcam using mpjg-streamer and PIR  motion detector board connected to GPIO pin (reset) on Bifferboard with Debian. Motion detector shell script runs in an infinite loop and every second checks GPIO pin level. Shell script is started with a crontab. Unfortunately, within a few minutes this shell script job disappears from job list "ps -x" . And I notice, if there are more things running then processes dissapear from "ps" list faster. But no error message appear. Could there be an issue with not enough RAM. Or it is a bug. "free" shows only 3 MB free and some swap is used. May be someone else has seen similar behaviour. This setup consumes 4 W power from wallplug, not quite 1 W as expected."

Repply:
"This is more a Debian Linux problem, than something related to the Bifferboard.
You need to run "dmesg" and see if the kernel killed your process 
because of low memory issue."

dmesg shows nothing. 
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