Hunter S. Thompson (July 18, 1937 - February 20, 2005) was a journalist best known for the "Gonzo journalism" style, where the author of the article is central to the story and writes a first person account of their personal experiences.
Thompson rose to prominence in 1967 when his book "Hell's Angels: The Strange and Terrible Saga of the Outlaw Motorcycle Gangs" was published. After writing a well received article on Motorcycle Clubs, Thompson spent a year drinking and hanging out with the Hells Angels Motorcycle Club in order to write a first-hand account of their activities.
Thompson's problem with alcohol and drugs was widely known, largely due to his intoxicated appearances during his book tour, which is why Jimmy joked that Thompson was the only person he could think of who might have taken a large amount of MDMA at 8:00 AM in the morning.
The agents consider the victims very expensive sneakers to be a clue. The plot line involving a computer key that can break any password is drawn from the plot of the movie Sneakers (1992).