Well, if you're running SSH on both
ends, you can use scp (check the
man page.) I have my
OSX PB box (at home) set up to
allow ssh connections (telnet and FTP
are both off), and I send work home
from my office computer using scp
all the time.
For command line FTP, the PB also
includes ncftp, a very nice
ftp client. It has a few niceties
over the standard ftp client, such as
support for bookmarks and a nice
progress indicator.
Also, wget is included. wget can
retrieve files from both ftp
and http url's. I often use
it, in conjunction with the "at"
command, to grab a file from a
busy server during the wee
hours of the night.