Shareaza hasn't had an update for 2 years, but still gets several thousand downloads a week.
Envy is an active developer fork of Shareaza, previously maintained as PeerProject.
Envy 2.0 was just released after 2 years of quiet work, and ready for feedback from the community. Do us a favor and try it.

Also of interest here should be the GetEnvy.com/archives - Mirrors of lost gnutella and Shareaza related sites.