It perfectly is, simply extract the zip on the usb stick and run the program, it still depends on an installed java.
To get rid of this dependency you could also add a java jre to the program directory with the name
jre, a detailed instruction can be found here:
http://wiki.eclipse.org/FAQ_How_do_I_run_Eclipse.
With the workspace selector you can choose the workspace. So you could have several platform installations on the usb stick (like mac and windows) and use one workspace.
greetings.
