Body Armor as Hit Points: The armor that you buy in service shops serves as extra points for your rather fragile cabbie. There are three varieties of armor in the game, but even then the protection isn't enough to deter bullets and explosions that your cabbie will endure. It seems that armor here in this game is Made of Plasticine, as if the game wasn't hard enough. Oh, and the other two armor versions won't be available until you finish all missions in the respective level that you're on ( the second version of armor isn't available until you're in the second level while the third won't be available until you're in the fourth level). Skirts dangerously close to Armor Is Useless.
Drives Like Crazy: The mooks in their cars do this to you if you get in their way. You, too, can likewise do the same, though it's better to do it on pedestrians unless they wave their hands at you for a fare.
Ejection Seat: You can eject your current passenger out of the car, while still moving. The Manual even comes with a handy table that shows the force of the impact in relation to speed. In some missions you have to do this with bombs.
Emergency Weapon: Your headlight-mounted "Hood Guns" are fast-firing machine guns that are useful for a little while as your main weapon. You're going to want to upgrade to something better fairly quickly. You always have these equipped, however.
Escape from the Crazy Place: The main goal of your player character, whose only means of escape are through underground tunnels that can be accessed only by OmniCorp passwords for completing all missions from the respective maps.
Everything Trying to Kill You: And yes, the spike traps, mines, and walled defenses at the edge of the maps can harm you too if you're not careful. Although it's partially averted with other taxis and some pedestrians either minding their own business or calling you to hitch a ride.
Expy: Although there's hardly some characterization about Drake Edgewater, he's essentially Travis Bickle with an Iron Woobie streak who justifiably thinks himself as the Only Sane Man in KEMO city, and wants to get the hell out of the corrupt city for good which he eventually does.
Frickin' Laser Beams: The Fusion Boy is a fusion gun that fires bolts of energy. It has a Charged Attack that can destroy certain vehicles in one hit at the cost of draining 3 cells when fully charged. Not until the second level will you be able to get it from the weapon shops.
Gatling Good: The Punisher (no, not that one [even though he probably will get wet dreams about the weapons and psychos in this game]) is a miniaturized Gatling-style revolver cannon that can hold up to 300 rounds. Then there's the even more powerful variant, the Banshee, which eats up ammo like a starved animal and will not appear until the third level.
Glass Cannon: Armor upgrades aside, your car can dish out a whole lot more punishment then it can take. Keep moving or die.
Gorn: This game was known for its gratuitous violence, causing a bit of a stir back in those pre-ESRB days.
Hover Car: All the cars in the game use anti-gravity propulsion, save the tanks seen in the sequel. They are tied to a power grid embedded in the roads and run on batteries whenever they go off-road.
Kill It with Fire: Your car can mount a hood-mounted flamethrower that can easily cook other vehicles as well as turning pedestrians into human barbecue. It won't be available until the third level, though.
The low-level version, the Fire Belcher, is essentially a moderately powerful incendiary-tipped artillery launcher, available from the start of the game. Have fun trying to aim it, though.
Macross Missile Massacre: You can mount missile launchers for your cab, but only one particular version that is only available once you reach the third level can launch a missile which has the ability to split into multiple warheads that can ravage a vehicle in one hit, and it's rather pricey to get, especially its ammo.
Mega Corp.: The aptly titled OmniCorp, who use less than scrupulous methods of keeping KEMO City under control.
Nintendo Hard: Between the limited number of hits you can take (forcing you to spend a lot of money on repairs) and the sometimes miniscule monetary awards, not to mention that every single mission is a Timed Mission, this game doesn't screw around. Road Warrior was a little better about this.
Nitro Boost: A variation: the booster is powered by argon cells that cost a hundred bucks a pop when going to service shops. It can be somewhat useful for certain missions that you have to complete, especially given the sometimes short time limit in the missions.
Precision F-Strike: You can taunt at other people with a button that has you utter out, "Up yours!"
Save Scumming: Really, you're going to have to save your game quite often, as the game's mooks and traps can quickly cut through your car's armor like a hot knife through butter. Also, the missions can have a rather short time limit depending on how far your car is from the actual location.
Sequel Hook: The ending of Quarantine suggests that OmniCorp has taken severe damage to its assets after Drake had foiled their plans and escaped the city, and they vow to take revenge on Drake. Cue the plot of Road Warrior.
Shotguns Are Just Better: You can mount a shotgun for your cab and it does pretty much what you expect a shotgun to be. Except it's not a Short Range Shotgun and it skirts into Game Breaker territory thanks to its near-unbalanced power and dirt-cheap price for its ammunition. It is available once you get to the second level and appears in the later maps from that point on.
The Immune: Drake himself, and anyone still sane enough to pay the cab fare.
The Taxi: Quarantine was the original Crazy Taxi, before Crazy Taxi came along. It would have been more aptly titled since this game has you gaining fares in a city run amok and your car equipped with the best weaponry the city can offer.
The Virus: Hydergine 344, originally meant to pacify would-be criminals, fries your brain and turns you into an Ax-Crazy psycho.
Timed Mission: Every single mission is this. Depending on how far the location is, you might end up with a frustratingly short timer while the city's layout can be very confusing if you don't check your map. Thankfully, the red arrow is there in the bottom right screen to help you.