mldonkey is a OCAML/GTK client for both eDonkey and Overnet
peer-to-peer networks.
(see http://www.edonkey2000.com/ and the 'edonkey' ports)
(see http://www.overnet.com/)

It is separated into a core with telnet and web interfaces, and
brings a GTK GUI (see the separate mldonkey-gui port).

Other features over the original eDonkey client are:
- better stability
- faster operation
- much better control
- saves its current state, checksums and known peers 
  (instead of starting from scratch every time)

WWW: http://www.freesoftware.fsf.org/mldonkey/