I just released
RocketCake 2.1, that's the free responsive website builder I am developing.

It now has support for SFTP, which it can use when the "publish to internet" button is used. It then automatically uploads your website (or the changed items) to your server with one click.
It was quite a lot of work to make it possible so that people can write sftp:// instead of ftp://. A lot of work for just one character difference. :)
Unfortunately, there is a lot of bureaucracy related to the US law for crypto exports. RocketCake is a free app, and I don't have the time to jump through all that bullshit, so RocketCake on the Mac App Store simply doesn't support the SFTP feature for now. I think it isn't worth this. If you want SFTP support, you can still use the version from the website instead.