See http://www.extragsm.com/blog/2014/12/03/connect-esp8266-to-raspberry-pi/
I used the B+ model and failed. I tried minicom and picocom so I will write this mornings effort off to experience.
There is an interesting follow up article at http://www.extragsm.com/blog/2014/12/16/use-esp8266-module-as-a-wireless-switcher/ Would have been nice follow up project, doing useful things with the RPi
Hope to have a cable tomorrow, so will go back to what I know works.