There are a lot of FTP software choices out there for Mac OS X. I personally use Cyberduck, but for those wanting a bit more, you really should check out the exhaustive feature list of Yummy FTP. In its latest version, it becomes fully Leopard compatible, with some extra goodies thrown in for good measure. You get Bandwidth Control, Free FTP Alias Droplets, and a Dock Menu to name just a few. $25 buys you a single license.
