Well Scientology is an evolution of Dianetics, which was a system created by L Ron Hubbard that talked about the immortal soul, or Thetan. In fact the parts about Xenu and the hydrogen bombs in Volcanoes is not the biggest part of the faith. However, it is true that it's become rather infamous, as it engaged in a huge-scale infiltration of the government to destroy evidence against the Church, and also tried to make it look like one of their biggest critics made bomb threats.
Cargo cults are Pacific island beliefs in the magical properties of industrial goods. They construct airstrips in an attempt to get cargo planes to airdrop such goods where they live, like they did during World War II. Notable pop culture instances of this are the Coke bottle in The Gods Must Be Crazy and the New Guinean's question in Guns, Germs, and Steel. The main point of G, G and S is that goods and resources are not distributed evenly, which is a central point of Cargo cults (the white people have too much of it).
Adidam is a cult surronding the personality of Jamaican Adi Da, who believes he is a divine incarnation, who has reached the final (seventh) stage of realization, ahead of other famous religious figures. It is vaugely pantheistic in nature, and claims two thousand members worldwide.