I used to write small Java MIDlets using just GNU Emacs because the laptop I was using at the time was too old and slow to run NetBeans.

I have to say that since the Javadoc format for documentation is the best format ever, I was productive anyway.

Actually, it made me get very very quick at browsing documentation and appreciate it.

Also, by browsing documentation manually, I got to discover many neat stuff within the default-provided Java packages.

... Did you know you can do neat stuff with java.awt.Robot? ;)