How to set up a Raspberry Pi so that VNC starts on boot. Mostly from http://myraspberrypiexperience.blogspot.co.uk/p/setting-up-vnc.html

rpi-vnc-on-boot.md

Starting VNC automatically on a Raspberry Pi

sudo apt-get install tightvncserver
vncserver :1 -geometry 1280x800 -depth 16 -pixelformat rgb565

• Set up a password for access (optional)

sudo vi /etc/init.d/tightvncserver

• Paste the contents of the file below (tightvncserver.sh) into this new file.

sudo chmod 755 /etc/init.d/tightvncserver
sudo update-rc.d tightvncserver defaults

Done.

tightvncserver.sh

### BEGIN INIT INFO
# Provides: vncserver
# Required-Start: networking
# Required-Stop:
# Default-Start: 2 3 4 5
# Default-Stop: 0 1 6
# Short-Description: Starts VNC
# Description:
### END INIT INFO

# First configure the user you want to run this under - this will generally be pi, unless you've created your own users
export USER='pi'

eval cd ~$USER

# Check the state of the command - this'll either be start or stop 
case "$1" in
  start)
    # if it's start, then start vncserver using the details below
    su $USER -c '/usr/bin/vncserver :1 -geometry 1280x800 -depth 16 -pixelformat rgb565'
    echo "Starting vncserver for $USER "
    ;;
  stop)
    # if it's stop, then just kill the process
    pkill Xtightvnc
    echo "vncserver stopped"
    ;;
  *)
    echo "Usage: /etc/init.d/vncserver {start|stop}"
    exit 1
    ;;
esac
exit 0

The script is missing a shebang. The following line should be inserted above line 1:
#! /bin/sh