OnionCat is described as 'Creates a transparent IPv6 layer on top of TOR's hidden services. It allows users to anonymously access Internet services. It transmits any kind of IPv6-based data transparently through the TOR network on a location hidden basis' and is a anonymizing network in the security & privacy category. There are more than 10 alternatives to OnionCat for a variety of platforms, including Mac, Windows, Linux, Android and BSD apps. The best OnionCat alternative is Tor, which is both free and Open Source. Other great apps like OnionCat are I2P, Hyphanet, Nym and GNUnet.