Symella is a Gnutella client for Symbian smartphones.
Gnutella is a Peer-to-Peer file sharing network system with many clients (and servers) available on various desktop operating systems (for desktop Gnutella clients check out this site).
It is used for exchanging files, especially music, MP3 files. Because mobile phones have limited bandwidth and small memory cards, this client focuses only for downloading, not sharing.
It is available on Series 60 and Series 80.
You can find it here: symella