After a few days of tinkering and a few days of waiting for the right parts to arrive I've finally managed to connect an Arduino board to a Nokia N800 internet tablet. First steps towards the Mlab robot.. I was really happy to find out how hackable the internet tablets are! Although there are numerous tutorials around the web, I'll put a short description of what I did before I forget:

Steps to connect N800 to Arduino

1. update N800 to OS2008
2. install rootsh to gain super-user access
3. install USB Control (enable Chinook Extras repository)
4. enable host mode through usb control
5. get a female type A-female type A USB connector. You might need to solder your USB-USBmini cable a bit if it's only slave mode. I bought one cheap from and it seems to work both ways out of the box. I guess you can also use an external power source if you don't want to solder your cable(?).
6. get kernel modules for USB Serial communication and FTDI chips from http://fanoush.wz.cz/maemo/modules-rx-34-2.6.21.0.tar.gz

7. unpack and install kernel modules as root with

   insmod usbserial.ko

   insmod ftdi_sio.ko

8. plug in your arduino

Extra: Python testing

1. get PySerial and install it. You can also just copy the python module from some *nix computer (I just copied mine from my linux box)

2. run this:

   import serial
   
   ser = serial.Serial('/dev/ttyUSB0', 9600)
   
   while 1:
   
       print ser.readline()
   

you should see whatever your arduino chip is printing.

Voilá! You have a connected a very flexible development board with a very hacker friendly, touchscreen enabled linux computer! Think of the possibilities :)