I have written a lot of small utilities in java that I store on my USB flash drive. The problem is that not all of the computers I work on have a jre. I have been putting the JRE installer on there and installing it on the machine everytime I need to use one of my utillities. My question is is the JRE self containing? Does it put any dll's in the System32 directory, or anywhere else? If yes, then is there a small stripped down version of the JRE that will run from a single directory?