I've been using a version of the excellent LFTP (v3.7.6), command line FTP client for Windows as part of a more complex backup program I've written.  

Recently, my program stopped working as expected, so I began investigating.  One line of investigation took me down the route of updating the LFTP version I had installed - not as easy as I'd hoped!  In fact, it looks like there's no-one who maintains a Windows build of LFTP anywhere on the net (I couldn't even find the version I'd been using again), so I had to build my own using CYGWIN.  This is not exactly complicated, but it was a waste of time that I didn't have, so I'm posting my build here which'll hopefully save someone else an afternoon!  It is built with SSL support and you will need to extract all of the files in the archive in order to use it.  It's compressed using the increasingly popular 7-Zip.

You can add all of the files to the %windir%\system32 folder to use the program from any folder on the system, or simply run it directly from any folder you choose.

For help and usage instructions, see the LFTP homepage where there's plenty of support and links to instructions available.

[UPDATE v423 build updated with config file - December 2011]

Download Link:  lftp423win.7z (Dec 2011)

Download Link:  lftp407win.7z

ehcanadian's 4.3.5 Build: http://ham-tech.net/tools/lftp_v4.3.5_win32.zip
md5: 213eeb88e8478ef012ed06c4f33ee27f