eMule is a filesharing client which is based on the eDonkey2000 network but offers more features than the standard client.
Some of the features of eMule are:

Clients use several networks to create one reliable network. (ED2K, Source Exchange, Kad)

Kad is now in an open testphase, eMule v0.42 can be enabled to use Kad

eMule’s Queue and [...]

FileZilla is open source  FTP client and server software distributed free of charge under the terms of the GNU General Public License.
Features of FTP client:

Supports FTP, FTP over SSL/TLS (FTPS) and SSH File Transfer Protocol (SFTP)
Cross-platform. Runs on Windows, Linux, *BSD, Mac OS X and more
IPv6 support
HTTP/1.1, SOCKS5 and FTP-Proxy support
Network configuration wizard
Configurable transfer speed [...]