The power leechers may remember LeechFTP from the german Jan Debis. A very cool FTP tool with the possibility of multiple server connections and multi-threaded transfers.
Development stopped about 10 (omfg) years ago and sadly some major bugs were never fixed.
After a lengthy search (hmm…this happens too often in the last time. Maybe I need a howto google) 🙂 on the net I found a alternative – though development seems to have stopped too.
The name is FtpCube – it´s Python based and still beta, but works good so far. I´ve contacted the developer – let´s see if there´s a chance for version 1.0