For anyone interested in a simple portable file splitter-
I took JFileSplitter (project page: https://jfilesplitter.dev.java.net/) and compiled it to an exe using JSmooth (project page: http://jsmooth.sourceforge.net/). It works perfectly in executable form. JFileSplitter is GPL'd and the author gives permission to modify and redistribute the program. (Run it and go to Menu -> About) The executable can be downloaded (zipped up) at ftp://anonymous@kmbb.org/downloads/JFileSplitter.zip.