You will need a bag to carry this stuff in.  I would recommend a wheeled computer bag or one of the big shoulder-mounted computer bags like Nerino Petro uses.  He’s got several posts at his blog Compujurist with good tips.  Anyway, after you have the bag, you will need:

1.  A good laptop that is fully synched with your system or a netbook holding all your software and an external hard drive that is fully synched with your system.
2.  the charger for the computer
3.  An internet cord
4. A good extension cord
5.  a smart phone
6.  a wall charger for the phone
7.  a car charger for the phone & if possible for the laptop
8.  some small tools to fix things that will break
9.  duct tape
10.  a wireless card for the internet
11.  a radio
12.  batteries for all and
13. eyeglasses