All these “socialists” since Colins have this much in common that they leave wage labour and therefore capitalist production in existence and try to bamboozle themselves or the world into believing that if ground rent were transformed into a state tax all the evils of capitalist production would disappear of themselves. The whole thing is therefore simply an attempt, decked out with socialism, to save capitalist domination and indeed to establish it afresh on an even wider basis than its present one.
https://www.marxists.org/archive/marx/works/1881/letters/81_06_20.htm
soulseek is the most known and used nowadays as far as i know. it is mostly used for music and film