* ftp://ftp.isc.org/isc/ – also available as http://ftp.isc.org/isc/
* ftp://ftp.oreilly.com/pub/ – only available as FTP
For the O’Reilly URI, it’s convenient to be able to click on directory links in the browser and then open HTML and PDF files without requiring another program.
So, it’s nice to have native FTP handling in Firefox for the odd time I’d use it but I can understand why Mozilla decided to remove it.