This is not really a trick of any kind, but it is easily missed because no part of it is required to beat the game, and you can only find out about it if you spend a long time in the Matrix, hunting around for data more or less at random. The CHERNOBYL side quest consists of five clues in the form of datafiles, and a final run against the federal government. The first part of the quest is putting the clues together. You must enter the networks of the five biggest corps in Seattle—Ares, Aztechnology, Fuchi, Mitsuhama, and Renraku—and download datafiles containing communication among the corps that expose a vicious plot to band together and control industry and government. Each file will reveal a little more about the corps' plans, as well as provide a small part of a passcode of some kind.