If you are not interested in becoming a better software developer / engineer, you do not need to read this post. However, if you have an inner desire to improve your skills (with minimal investment), please read on...
Static analysis tools are a great way to becoming a better software developer. These tools have the ability to scan your source code, and give you feedback that can make your applications run faster and less prone to errors.
FindBugs, by Bill Pugh and his team, is a great example of a static analysis tool. After listening to his interview on the Java Posse, I was very interested and excited to give FindBugs a try. After installing it as a plugin for Eclipse, I ran it on a random project that I had in my workspace. It notified me of some areas where the code could be improved, but it also gave a very clear explanation of why it was making the suggestions it made:
So if you are interested in becoming a better software developer, I don't think you can get a better return on your investment than employing FindBugs, or any other static analysis tools.