Using Google Spreadsheets and the Google finance API available with Google Apps script, I was able to automate every part of this except syncing it with my account (since there's no API to access my financial records.) All I have to do is click a button, and the cells change color based on whether I should buy, sell or hold.
Thank you for your help.
The current price of the share is fetched from another sheet using a vlookup. That sheet is populated by the script. The script is here! https://gist.github.com/2717042
The overall system is based on research I found here: http://seekingalpha.com/article/15134-the-seeking-alpha-etf-...
It's actually possible to simulate a browsing session and have the App Script log in to your broker's site and scrape the data you need. Here is some prototyping code: https://gist.github.com/aaf74e50b9a281396722
Here is the scripting engine part: https://gist.github.com/2717042
It is incredibly useful in general, but definitely not news.