You're driving the Love Fist limo only to find out that it's a armed with a bomb, and the only way to not set it off is to drive fast, a la Speed, until the group finally disarms it. Hilarity Ensues.
The fact that Tommy is constantly annoyed throughout the whole mission makes it even more funnier. If you only watch one YouTube video of a mission in this game, watch this one.
Jezz: Tommy pal, you gotta save the band! Tommy: I'm getting bored of this. Jezz: Just keep the pedal to the metal! (later) Jezz: Which wire, Tommy?! Tommy: The green one.
You drive like a lunatic all over town, running over innocents, gun down several people including cops, SWAT teams, FBI agents, and cause massive destruction of property, all in broad daylight and in plain view of every law enforcement officer in town. You are eventually arrested, and as you emerge from the police station (minus weapons and a small bribe/fine) you can hear Rosenburg in the background, "Tommy Vercetti is an innocent man!"
The first phone call that Tommy gets after obtaining a mobile phone:
Unknown: Hey, uh, Leo, I think we have buyer for Diaz's merchandise. Gotta give them a ring, man, set up the deal, you know? Tommy: Where are you now? Unknown: You okay Leo? You sound kinda... different. Tommy: Just tell me where you are. Unknown: Who the hell is this? Put Leo on, man! Tommy: Leo's gone away for a while, he left me in charge. Unknown: Screw you, man!
This exchange from the beginning of the mission "Supply and Demand":
Diaz (screaming at his VCR player): Eject! Plastic crap! You doing this to ME?! Who do you think you are, you piece of plastic SHIT!?! Aaaaargh! SCREW YOU!!! (Diaz shoots up his VCR, Tommy walks in) Diaz: It eats my favorite El Burro movie, it die! What else could I do? Tommy: It's probably not plugged in. Diaz: What? (looks closely and sees that Tommy was right) Damn - no matter, I can buy a hundred more.
And just a little later in the scene, Diaz scratches his crotch with his gun.
Tommy's Italian goombas and their generic dialogue.
Thug 1: What should I do about her? Thug 2:Forget about her, Mario! Thug 1: I told myself, "Mario, take it easy!" Thug 2: You better tell him, Mario. Thug 3: Hey, it's Mr V!
Before the final mission, Ken talks about how he hates the prospect of him being a subject to Cement Shoes.
"I like fish. I love fish. I like them as pet in a bowl, or a food on a plate. But as much as I love them; I don't want to sleep with them!"
Early in the game, we usually get an inside look into Tommy's thoughts after a mission cutscene ends. Most of them are full of snark.
(Upon told on getting a suit to attend a fancy party - by Rosenberg of all people!) "Who does that guy think he is? Now I gotta dress like a chump as well as hang out with them? (Genuinely hurt) I like this shirt..." "Great, more crap to wipe up! What did I do in a past life to deserve this?" "Lawyer pricks, rug-wearing pricks - I'm surrounded by pricks!!" "Abandonment issues?! What a freak... why can't I meet someone that's normal for a change?" "Dumb. Florida. Moron."
This bit from "Cop Land", where Tommy and Lance have to sneak into the mall and detonate a dud bomb (long story) by disguising themselves as police officers.
Tommy: Remember, smile at the other cops. Lance: Hey there, officer. Nice badge, nice badge. Tommy: Real smooth, Lance.
The "G-Spotlight" mission requires you to do a lot of Roofhopping on a motorcycle. Of course, there's the question of how you get a vehicle like that onto a rooftop so you can begin. Tommy decides to just drive straight into an office full of people, roll up to the nearest elevator, and ride into it when the doors open. In the elevator are a man and a woman, and they just stand there speechless as this stranger rides his motorcycle into their elevator and the doors close. Cut to security camera footage of the rising elevator, showing the man, the woman, and Tommy on his bike riding up in awkward silence. The doors finally open on the floor Tommy wants and he nonchalantly backs his bike out like this sort of thing is completely normal.
After the final mission, Colonel Cortez will call Tommy in a panic, asking him about some kind of awful rumor he's heard about Mercedes. Given how promiscuous Mercedes is, one would expect him to be upset over her sleeping around. It's not that—he heard a rumor that she was planning to become a lawyer.
The scene is capped off by Cortez telling Tommy he has to go meet somebody. Apparently, Cortez killed the guy's father in a coup, so he has to be polite.
Couzin Ed, the Jerkass former DJ at V-Rock calls in at one point, apparently getting kicked off the station in favor of Lazlow. He has apparently left the hard-partying life of a metalhead, and now works as poorly paid job as a bus driver, which apparently causes some friction between Ed and his wife.
Tommy can drive any sort of car, truck, or motorcycle, and even fly a helicopter...but instantly dies when he touches water.