In my ongoing quest to get an free, lightweight and fast download manager with remote access ability for Raspberry Pi. I settled for Transmission to get torrent downloading and pyLoad for ftp/http downloading, however both of them have issues under limited resources of Raspberry Pi and had frequent crashes now and then.

After, a lot of research, tweaking and testing - I had finally found the best option for a perfect lightweight download manager on linux as "FatRat". Despite the name being FatRat, this open-source download manager for Linux is written in C++ and is slim on requirements, fast on performance and comes with all the bells and whistles one would need from an modern download manager including Segmented HTTP(S)/FTP downloads, FTP uploads, torrents and a super-fast web-ui for remote access.