Dave gave me something interesting to work on, (thank you), and so I did.
ftp and scp uploads.
But I have only been able to test scp, I don't have a writeable ftp server handy, so can't guarantee that one.
But scp is pretty cool. Give it a try.

e scp://login:password@whatever.com/home/mylogin/some_file
make some changes
w
q

It all works, but, as I mentioned on the chat group,
1. I can't use keys to ssh in; I have to specify login and password, which is kind of a pain. Is that a limitation of curl, or is there some other way to tell it to use public keys? Some sites only allow for ssh with keys.
2. I have to specify the absolute path, it starts from / not from my home directory. This is different I think from how ftp works. Also different from the shell scp command, so is confusing.

I haven't documented these in detail, not sure how they work yet, or even if ftp works at all.
I did add them to the quick list of commands, that you see by typing help.

The downloads, like all downloads, can happen in the background, if bg is set,
but uploads are always in foreground.
I think this is reasonable, you're more likely to ftp down a huge file, than to ftp up.

Karl Dahlke