Although I haven't had need to do so for freelance jobs, I do administer several Windows-based Sybase and MS SQL Servers at my day job.
I recently needed Java 6 to install an Eclipse patch. As you're probably aware, although Apple updated OS X 10.5 Leopard to Java 6 they probably never will provide updates beyond Java 5 for Mac OS X 10.4 Tiger. The good news is that if you're running an Intel-based Mac, you can keep your Java environment up-to-date with SoyLatte, which is part of the OpenJDK BSD-Port project.
The other morning, before I had my morning coffee, I fired up Eclipse and when prompted to select my Workspace, I entered my password and hit return. Still in a haze, I wondered why I was looking at the default Workspace. After restarting and seeing my password in the selected Workspace I finally woke up. D'oh!
I've been a Firefox for Mac user for many years, and before that Mozilla and Netscape. I stuck with Mozilla, despite the release of Safari, because I'd using it for email since Netscape Messenger.
I remember how excited I was when Mac OS X was initially released. Finally I had real development tools available on my platform of choice. I could run a web server with middleware to develop database-driven web sites on my laptop. The only problem was that although having Unix file management skills, at the time, I had absolutley no experience compiling the required Unix software from source.