Shout Out / Transmetropolitan

• Right in the title: 'Transmetropolitan' is the name of a Pogues song, and 'The Summer of the Year' is from that song's lyrics.
• 'Straight to Hell' is both a famous song by The Clash and a film featuring Clash frontman Joe Strummer and, again, the Pogues.
• The bodyguard for Kristin (the drug dealer/political consultant) looks a lot like Charlie Brown, even with a familiar-looking dog in his second appearance.
  • During a walk-and-talk where Spider is interviewing a group home manager about his wayward wards, the manager snatches a lit cigarette from, and subsequently flipped off by, a clear expy of Peppermint Patty.
• Quoth Spider (Cosplaying as Jesus):
  Spider: Messianic fuckheads are a superstitious, cowardly lot, and I must strike fear into their hearts.
• Expository Hairstyle Change - Vita Severn, the Smiler's campaign manager, explaining why she let her hair down from a pair of buns: "That haircut was all cultural buttonpushing (...) Made me look tough and smart, but also the underdog, fighting an evil empire as best I can..."
• The use of a three-eyed smiley face as an Arc Symbol is reminiscent of Watchmen's use of a smiley face with blood over one eye.
• One of Spider's panels in Issue 30 (when Detective Newton has a gun to his head) is an exact copy of Rorschach's final "DO IT!!!" in Watchmen.
• Issue 6's first page references an "intrinsic electric field".
• There's a sign for "the Church of Ennis" at the religious convention in the sixth issue. With a tag under it saying "Custer". Bottles of Ennis-brand liquor also make a few appearances.
• Another subtle one: the cigarettes Spider smokes are called "Carcinoma Angels"—which is the title of a story by Norman Spinrad, originally published in Harlan Ellison's 1967 anthology Dangerous Visions.
• In the issue "Straight To Hell", one of the rioters bears a distinct likeness to Wolverine, complete with gripping some sort of weapon that sports three jagged claws.
• Comedian and Actor Brian Posehn of Just Shoot Me! and Mr. Show appears at the bottom of one page, holding a brochure for "Insane Posehn's Used Porno Clones." His name also appears in a lot of background signage and graffiti.
• A lookalike of Lola from Run Lola Run is shown... well, running through a crowd scene.
• The same issue seems to sport a young Tom Waits in a crowd.
• "Spider's Thrash" features someone looking suspiciously like Tyler Durden walking through a crowd, with a billboard behind him saying "use soap." The demolition company shown later in the same issue bears the name of Durden Demolitions.
• Edward and Tubbs of The League of Gentlemen fame feature prominently in a couple of panels...just before Edward catches a bullet in the forehead.
• A newscaster near the end is named Tim Leherner. Tim "Telstarman" Leherner is a real person who got Ellis's attention due to owning 130+ versions of the song "Telstar" (though he looks nothing like the comic character).
• A billboard in "Here To Go" features a couple of faces who look an awful lot like Leela and Bender. Notably, the two share the setting of a future New York and depict it in a similarly parodic, exaggerated way, although Transmetropolitan came first.
• The Dice Bar has Duff Beer on tap.
• Oscar Rossini has a significant but not total resemblance to acknowledged fan Patrick Stewart.
• The gun Spider pulls on the phone and later Royce in the first issue is Han Solo's blaster.
• In issue 8, "Another Cold Morning", in the medley of scenes Mary beholds of the city, there is a woman with a chopper, and the exhaust on the chopper reads "Zed." In Pulp Fiction, Zed, who is central to Butch Coolidge's story, has a chopper.
• Spider takes a ride in a Bickle Cab.
• There's a sign for 'Aronofsky' on the side of a building in one issue. Director Darren Aronofsky is another famous fan. There is also a billboard for someone with the first name "Tappy," advertising a Month of Power and with the slogan, "Juice By You!" This is a reference to the infomercials in Aronofsky's Requiem for a Dream, in which Tappy Tibbons advertises his Month of Power with the slogan "Juice By Tappy."
• The ever-changing slogan on Yelena's shirt occasionally reads GloomCookie.
• In the scene in the chapter "Two Fisted-Editor" where Spider is sitting in a wetsuit with a bowl of frogs to throw at the TV, one of the frogs is on the floor next to his feet, wearing a tiny top hat.
• Two Pixies' songs, "Gouge Away" and "Wave of Mutilation," are directly referenced, the former as the title of one of the comic's collected volumes, the latter as an appropriated quote in one of Spider's columns.
• Tank Girl can be spotted on the sidewalk in one panel, helpfully wearing a t-shirt reading "Tank Girl."
• Qi threatens her laptop, which replies, "I'm sorry, Qi, but I'm afraid I can't let you do that," quoting HAL from 2001: A Space Odyssey. It also quotes George Washington by proclaiming, "I cannot tell a lie," before making a confession.
• In part one of the Dirge storyline, a billboard saying "Breaking News: Dr. X Threatens Earth" can be seen, referencing the villain of the British Action Man franchise.
• After the announcement of the vice president choice enrages Spider, he shouts at Yelena "Is the machinery cued? Are all of our information devices set?" and she replies "Atomic batteries to power! Turbines to speed!"
• Shortly after the above, he tells Yelena to start the machines. "Throw the switch, Igor! Throw the fucking switch!"
• The "alien colony in old Vilnius" that Fred and others mention in passing is also brought up in Ellis's Lazarus Churchyard.