) has a Linux version that's tested on Fedora, Ubuntu, AMI Linux, and Mint. Plus it has a well-developed and well laid out GUI, if you prefer GUI management over terminal. It's written natively in C/C++ so it doesn't suffer from the performance losses you usually see with servers written in Java. It has a web interface that allows for transfers using HTTP/HTTPS, and in the Silver and Gold editions there's a free applet that supports multiple concurrent transfers in the browser. Finally, the Gold Edition has a remote admin console that works via the browser.