The one thing I've struggled with since going over to the Mac side is a decent FTP client that actually works. Cyberduck crashes like a blind chav in a Mondeo and the 'classic FTP' would stall more often than a seven year old chav on a council estate...
Then I found...
Fireftp
http://fireftp.mozdev.org/
It's a Firefox add on, so you open it in your Firefox browser in a new tab. It works on Mac & PC so it's nice to have the same style in both formats. It's free and, so far, it's stable & quick. Needs Firefox 3.0.1 or later but then if you use Firefox, you need that too. Well worth the money!*
*so good that if I'm still using it in a month, I might even send the guy $10