For the installation process you need to get the flasher tool from http://tablets-dev.nokia.com/maemo-dev-env-downloads.php
There are two images available, open Meego image and one with some closed Nokia proprietary binaries.
NOTE: With the open image the battery management is not functional so you may cause damage to your device.
Get the open Meego image and also the kernel (zImage-arm-n900) from FIXME.
This image can be then flashed to the device:
sudo flasher-3.5 -f -k zImage-arm-n900 -r <meego.ubiimg>
There are following closed components available for Meego to improve the user experience with N900: