Miguel has a post about FTP clients and, while it veers a little from the kind of posts I make here, I wanted to chime in. One of the clients Miguel talks about is FireFTP, an Firefox add-on. I have been using it for about a year now on a regular basis, and I have to say that I absolutely love it. I tried some Linux options, including gFTP, but nothing beat FireFTP for ease of use.
When you download it, a screen comes up one time to ask you to donate through PayPal if you feel so inclined and are able. As you can read here, the developer isn't using this money to buy new toys. Half the money goes to help orphans in Sarajevo, Bosnia & Herzegovina. He keeps the other half to help his family, which includes an orphan from that area that they have adopted. So if you are in need of an FTP client, check FireFTP out. And once you do, please consider donating what you can. It is a good cause, and FireFTP is worth at least whatever you feel inclined to give!