Java and eclipse make a pretty fun development environment. Sure, there are the occasional text encoding issues, and the obscure preference setting battles, but all in all, it's really fun to be able to refactor my code easily and trace through stuff.
I've decided that the number one priority for my code right now is that it be clear and easy to understand. On a big project, it's really important. This year-long project has been really fascinating. I've never seen a project from requirements gathering all the way through to testing and delivery before. My previous experience has usually been midway into the life cycle of an application.
In particular with my current project, each section of the application has been handed off to a different team, so it's interesting to see what different teams have implemented for the same problem. The development styles are wildly different.