I like portable software. I carry around a bunch of them in my flash drive. I just found out that both Java and Eclipse are available as portable versions at PortableApps.com. The Java version they have is Java 6 update 14 but Eclipse is stuck at 3.4.2.
Eclipse uses portable Java, so Java need not be installed in the PC to run it. Nice. The portable version has some trouble finding the workspace but once you correct the path it works fine.
I updated the Eclipse binaries in to the just released 3.5 and it work great too. Nice way to take Eclipse and your work with you.