Eclipse is an SDK for Java. Though I doubt the Java VM itself will ever be portable, Eclipse even now needs no installation. I was thinking that the launcher would find a Java installation on the local machine and add it to the command line argument (Eclipse needs to know where Java is or it will refuse to open). It would work on any Windows machine with Java installed.
License for reference:
http://www.eclipse.org/org/documents/epl-v10.php
This has been discussed.
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R McCue
"If you're not part of the solution, you're part of the precipitate."