I built this for personal use. The development has been halted for a couple of years but it is still a very useful and competitive file manager. I think it's working well (except for UTF-8 display) but please test it out yourself.
Description: muCommander is a lightweight, cross-platform file manager with a dual-pane interface. It runs on any operating system with Java support (Mac OS X, Windows, Linux, *BSD, Solaris...).
Download muCommander Development Test 1 [4.5MB download / 5.6MB installed]
Development Test 1 (2015-06-12): Initial release