1. Computer Access (I know, duh!)
      If you do not have easy internet access then a laptop or netbook will be useful. For security reasons I would recommend mobile broad band. This is the most important item on the list.

2.  Stock Watch List
      This is your master cheat sheet. Put it somewhere you can easily access it. List the stock symbol and buy price. When the stock is close to your buy point, buy!

3. Written Strategy
      It must be written and accessible. Following your written rules will eliminate some emotion and will protect your capital. Never guess on your rules.  Write them down and follow them!

4. Cell Phone
    Not really a must, but can be very useful. A smartphone, like an iPhone, is not a replacement for a good laptop/netbook, but it can give you quick easy access. I have bought stocks sitting in my car waiting on my kids to leave school. Getting text message alerts on stocks is also useful.

Post your list of necessities in the comments. I would love to see how everyone is using technology and gadgets to do better investing.

Happy trading!