Antihero for Hire normally has the action taking place at night. When the hero has to get up during the day, he needs his coffee. He ends up spending most of the arc looking for some.
User Friendly uses this trope from time to time, particularly with the Crud Puppy.
Early strips of the comic have tech support member Greg harassed by a Kool-Aid Man-esque can of diet cola when he decides to try to cut back on caffeine.
"I just rewrote the Linux kernel!" "When did you learn to program?" "This morning!"
After attempting to make a truly Uninterruptible Power Supply powered by uranium, Pitr reveals that as of recently he's been making coffee with heavy water.
What's the first thing they restore power to after moving their operations into an abandoned nuclear silo? Nope, not lights... "Ahhh, truly dark roast."
Vanamonde von Mekkhan from Girl Genius spends all his time in a coffee shop in Mechanicsburg, and certainly does enjoy his coffee. He has even written a textbook on coffee preparation (under a pseudonym): Bean There, Done That.
In another strip, someone offers Faye coffee first thing in the morning, and she drinks it straight from the carafe.
From The Order of the Stick, the prequel book Start Of Darkness reveals that before he became a lich, Xykon loved coffee (he even refused to let Redcloak and Right-eye tell them about their plan until he had some), and extolled the virtues of bad coffee (as he puts it, when you drink truly horrible coffee, you force yourself to re-experience every good cup you've ever had to block out the slop you're currently pouring down your throat). When he tries to drink his first cup of coffee after becoming a lich and discovers he no longer has a sense of taste, he reacts... poorly.
Lynette from Sharing a Universe quickly got hooked on the stuff and turned herself into "The Coffee Hunter" stalking the city after those precious beans when Alison decided to intervene and stop supplying her addiction.
Florence Ambrose tends to take exception to having her coffee taken away, as only a carnivore can. She also explicitly cited the availability of coffee as a benefit of restoring power to Sam's ship. Amusingly, another strip indicates that she can't actually drink coffee due to her canine physiology, but as an engineer she craves the smell of it.
In the Feb 5, 2014 strip, the coffee maker still brewing is implied to be the reason that the compound where Dr. Bowman is being held wasn't able to get above 50% readiness in under 60 seconds.
In General Protection Fault, part of the test to see if a geek is 'The One' is a test of caffeine addiction. Fooker passed it by enjoying coffee that has congealed to the consistency of tar. Sharon passed it by chewing coffee beans and washing them down with more coffee.
In Sluggy Freelance when Torg and Riff briefly got regular 9-to-5 jobs they became coffee zombies in the morning.
Later, making everyone addicted to high-octane "coffee" (that is explosive in its undiluted state) is just one form of Government Drug Enforcement in 4U City. And cutting off the coffee pipeline sets off a massive revolution.
White from Grey is..., especially in the mornings but it seems to be his drink of choice all the time. When he first gets back after two years away, the first thing he does after greeting Black is search the house for coffee
In Blue Milk Special Darth Vader is addicted to coffee (which he drinks with a straw out of his favorite Star Trek mug), to the point where a) he had a temporary truce with Admiral Ackbar so they could get coffee, b) he placed a higher priority on getting the coffee machine on the second Death Star fixed than the second Death Star, and c) it triggered his Heel–Face Turn, as Palpatine forcing him to fight Luke led to his beloved 'Muggy' getting shattered.