!update - model A, PiCam, B+, A+, Pi2 and now Zero alert!

after writing Raspbian os to sd card and powering up with monitor keyboard and mouse :
- raspi-config (starts automatically on first boot) - expand_rootfs
- change pass
- change_timezone
- change_hostname
- ssh (enable)
exit from raspi-config and startx to config wifi noting the ipaddress. you can then log in headless via ssh.
(It would be nice to find cmd to configure wifi?)

(untested)
# in /etc/network/interfaces
- auto wlan0
- iface wlan0 inet dhcp
- wpa-ssid "whatever"
- wpa-psk "encryption key as it I typed it in on the router"(/untested)

On Linux I can mount the SD card before it goes in the Pi and alter the file without needing to go wired.
I wonder how much config I can actually do this way without actually putting the card in the board.

Configure multiple wifi networks from cmd
sudo vi /etc/wpa-supplicant/wpa-supplicant.conf

add the following:-

ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1


network={
         ssid="networkname01"
         psk="networkpassphrase"
         id_str="networkname01"
         }
network={
         ssid="networkname02"
         psk="networkpassphrase"
         id_str="networkname02"
         }

sudo vi /etc/network/interfaces

auto lo

iface lo inet loopback
iface eth0 inet dhcp

allow-hotplug wlan0
iface wlan0 inet manual
wpa-roam /etc/wpa_supplicant/wpa_supplicant.conf
#iface default inet dhcp
iface networkname01 inet dhcp
iface networkname02 inet dhcp

usb-rs232 comms??

On Raspbian the shell is by default accessable on the serial pins of the pi so we can again headlessly log in to a command line by using PuTTY and a Prolific PL2303HX usb to serial connector like THIS one.

It should be noted that the red power connector can be used to power the pi from the usb with usb current limitations. A better power supply would be to use the usual power inlet and disconnect this red pin.
DO NOT TRY TO POWER THE PI USING BOTH METHODS AT ONCE UNLESS YOU WISH TO USE THE PI AS A SMOKE MACHINE.

Physical connection to the pins on the pi from the nearest corner outer row:-

red - 5vdc(+)
space - NC
black - common(-)
white - data tx
green - data rx

There are a number of usable terminal emulators, I spent a great deal of time using Hyperterminal on earlier windows trying to send DTMF tones and commanding modems, but PuTTY seems to be as good as anything. In the config, select "serial" in the connection type, and it should be possible to find the COMPORT in the windows device manager. Older computers used d type connectors for serial populating com1 to com4 and usb would start at com5, however my current pc has allocated com4.

Baud Rate - 115200
DataBits - 8
Stop bits - 1
Parity - none
Flow Control - XON/XOFF

To disable the getty on the serial pins either for security or to reuse the pins:-
sudo vi /boot/cmdline.txt
remove the "console=ttyAMA0,115200" and "kgdboc=ttyAMA0,115200"
leaving the line looking something like this:-
dwc_otg.lpm_enable=0 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline rootwait
then
sudo vi /etc/inittab
At the end of the file comment the following with a hash # to look like this:-
#T0:23:respawn:/sbin/getty -L ttyAMA0 115200 vt100

save and reboot.