Hall of Fame

[the_mod]

The best of the best of free networking software.

Filezilla - my favourite ftp client, there's also Filezilla server as well.
http://filezilla-project.org/

Putty - great for accessing remote servers/routers by ssh, ftp, telnet, serial
http://www.chiark.greenend.org.uk/~sgtatham/putty/

VNC - remote desktop access (used in my school to remote desktop clients that are not part of the managed service and therefore can't be accessed by windows remote desktop)
http://www.realvnc.com/

WinSCP - ssh/ftp client - upload/download files with an explorer type interface
http://winscp.net/eng/index.php