Comfortably useful peer-to-peer file sharing utility. Not BitTorrent but easier to use. LimeWire has a Pro version, too. Now it costs money to steal files.

LimeWire is a fast, easy-to-use file sharing program that contains no spyware, adware or other bundled software. Compatible with all major platforms and running over the Gnutella network, LimeWire’s open source code, is freely available to the public and developed in part by a devoted programmer community.

9WR - LimeWire: Elegant P2P file sharing utility for Mac, Windows, Linux.