well,i really use ftp because i repair pcs and sometimes i need to download patches and programs from my pc. when i'm at school,i have some works, i upload them to my server and i finith them at home. it's amazing!
my brother also uses ftp to download files and music.
i'm behind a router and with sympatico hsi (!!!) and i enabled dmz to my modem and opened ports with my router + i have a firewall installed in my pc.
i don't worry about opened ports,you could have opened ports if you are directly connected to the internet like cogeco cable services