FreeFileSync is a muti-platform folder comparison and synchronization tool that comes with some very useful features like support for multiple folder pairs, binary files support, can create "batch files" which can be used to automate folder synchronization and others.

When the first Lubuntu ISO came out (LXDE based Ubuntu), it was said that it's purpose is to be faster than Xubuntu:

The Lubuntu project started in March 2009, with the purpose of creating a lighter and less resource demanding alternative to the Xubuntu operating system, using the LXDE desktop environment. The ultimate goal of this project is to join the ranks of Kubuntu and Xubuntu and become an officially supported derivative of Ubuntu.

And many argued, but now, Linux-Mag published some data which compares the memory used by Ubuntu, Xubuntu and Lubuntu in 2 ways:

1. The first test is simply to check how much memory is used after a fresh boot of the respective live CDs, all the way into the default desktop (first graph below).

2. With the every day applications loaded, including a terminal, file manager, calculator, image viewer, text editor, archive manager, web browser, mail client, chat program, bittorrent client, audio player and video player (second graph below).

Take a look at the two graphs: