I find that using SSH to a real computer is the best way to manage files, especially if you are digging beyond your home directory where breaking stuff is possible, if you want a sort-of gui install mc (midinght commander).
Since I like to manage by SSH I redommend installing:
sudo apt-get install ssh wget mc links(or lynx) screen

links and/or lynx are web browsers, wget is a web link downloader whith many options and is good for scraping websites and bulk downloading

I have never wanted to learn ssh from computer cause I like to think that N900 has all it needs. If I need acomputer to work with N900 then it like spoils the glamour.