Al the top right corner of the Home sidebar you will see a number than indicates how much memory is consumed by the program.   


Please note that since Filetopia relies on Java, a virtual environment it can upon a occasion use a large amount of memory. If you have many windows or lists open, closing the ones you are not actively using will help decrease memory usage. When memory usage goes over 500Mb,  the color will change to orange. When it goes over 1Gb, it will change to red.


While the figure updates periodically or every time you click a window, to ensure its accuracy click it.  This will force Java to release all unused memory and will give you a realistic figure of what your current memory usage is.   


The figure displayed is the amount that is used by the program itself, but it is worth noting that the Java Runtime Environment uses memory to run itself, so the amount you see in your Windows Task Manager will aways be a bit higher than what is listed on the home sidebar.