A series of popular score attack racing games. The Crazy taxi franchise had its roots in the arcade, and eventually found its way to the Dreamcast, where its popularity really took off. Aside from being extremely fast paced, it serves as an excellent example of successful in-game advertising. Sporting locations like KFC, Tower Records and Pizza Hut, Crazy Taxi's blatant and prolific product placement actually found favor amongst most gamers, as the inclusion of real products made the game's environments more authentic.
Overview
The Crazy Taxi series is a franchise created by developer Hitmaker and publish by Sega. It was release in the arcades in 1999 and gain a lot of popularity; as a result, it was ported to the Dreamcast in 2000. It became one of the best selling games on the system (Reaching "Sega All Star" states), the game was also released on the PlayStation 2 and Gamecube. Several iterations of Crazy Taxi follow suit after the release of the original.
History
The series was created by developer Hitmaker. Kenji Kanno, the producer of the game, stated that he got the idea while driving along Japan one day; and got stuck in a traffic jam. He saw an empty lane and wanted to drive through with a "Good feeling."
Curiosity sparked within his mind when he develop a theory, if the same idea could work in a video game. He wanted players to assume the role of a taxi driver. At first his development team was against the idea, but they soon became won over as Kenji Kanno explained more about the concept.
He explained about the time extensions aspect of the gameplay, it would stray away from the "One-hundred yen for three minutes" which was the common format for arcade games at the time. That idea would make the game longer if players perform well. Soon, as things develop, it would become a winning formula.
The main objective of the gameplay of the Crazy Taxi series is about picking up a passenger and dropping them off at their desire location. But the series contains many techniques for the player to learn to earn extra cash and time. As a result of all this, the Crazy Taxi series has a lot more depth then originally precieved.
Crazy Taxi (1999)

The arcade version.
The original Crazy Taxi introduce many gameplay elements to the series. The player has the option to chose one of four cab drivers, they are depended on speed and handling. Another gameplay element being is the costumers, there are four type that are categorize in different colors - it represent their difficulty. Costumers will be hanging around the city with a dollar sign above them, they will be standing in the middle of a circle that is the parking zone. The size of the circle is depended on their difficulty, the easiest will be large enough for the cab to park; but the harder the difficulty will make the circle smaller. The player must also be careful on how he or she approaches the costumer or the costumer will run a couple of feet away from the parking zone which will cause the player to waste a few seconds getting in the cab. As a matter of fact, the cab driver will tell the costumer to hurry up and get in the cab.
There are three different rankings that the player will receive. While the player is getting to the destination, a count down will appear on top of the taxi cab, first the count down will appear in green, then in yellow, and then in red. If the player makes it to the destination on green, the player will receive the "Speedy" rank, it will give the player an extra five seconds added to the overall time to the game. If the time is in the yellow, it means "Normal," it will give an extra two seconds added to the clock. And if it's in the red, it means "Bad," the player will receive no extra time.

The original four cab drivers of Crazy Taxi.
Many techniques (Stunts) are use to either help the player in certain situations or to earn more cash. The "Crazy Boost" is a mechanic that will speed the cab up to reach its maximum acceleration. The "Crazy Drift" is a drift mechanic that is use to turn the cab 360 degrees, it is useful if the destination is in the opposite direction that the cab is in, and the player can more cash for drifting. "Crazy through" is another way to earn bonus cash, if the player gets a near miss - passing by a car. The "Crazy jumps" can be done by riding through ramps or hills with large slopes. All the stunts in the game can be tie together to earn more cash. The amount of cash will increase by fifty-cents, and it will increase even further if the player keeps it up; the chain will end if the player gets hit by another car.

Crazy Taxi.
As soon as the player earns more cash, the more difficult the game will be, more costumers will give the player less time for the player to get the location that the costumer wants to get to, and traffic will increase (Cars will actually be parked on side-walks). Once the player starts receiving normal ranks or gets to the desire location not as fast as the player wanted to (Even when the speedy rank is given), the player will begin a downward spiral to the gameover screen. At first (If skilled) the player can have his or her timer on a strong one-hundred seconds or over, but then it will deteriorate, the player will soon start to struggle to keep his or her time on thirty seconds or less.
Crazy Taxi 2 (2001)

The "Crazy Hop" really did change the strategy of the formula.
Crazy Taxi 2 was the final Crazy Taxi game to be released on the Dreamcast, at that same time, the original game was ported on the PlayStation 2 and later on, the Gamecube. Every gameplay method that was feature in Crazy Taxi was in Crazy Taxi 2, with a new layer of depth added to the formula. Crazy Taxi 2 added four new cab drivers to chose from, the cab drivers from the original do return as unlockables. Two new cities were created (heavily based on New York). A new gameplay element known as the "Crazy Hop" was added. The crazy hop is done with the push of a button, it helps the player in huge traffic jams that the player has trouble getting through. And the game gives the player the ability to pick up two to four costumers at once.
The way the both cities are structure defiantly makes good use of the crazy hop. There's a extensive amount of short-cuts that have to be taken in order to get to the desired location on time - which consist of jumping on roof-tops, though sometimes you will be jumping from one highway bridge, to another. When the player is driving to the destination, he or she must quickly examine the environment to know if there's a short-cut that can be taken. Certain short-cuts are pretty obvious, such as the arrow that naviagates you is pointing towards a short roof-top, but sometimes it can be a bit more complacated than that.
Multiple passengers can be picked up at once. Once the player does so, he or she must drop them off in different locations. The amount of money that increases for doing stunts will get multiply by the number of costumers the player has. But the player has to be careful on which location to head to first, he or she must keep in mind on which location is the closes first, and then do the same for the next locations. The new layer of depth does make Crazy Taxi 2 more difficult than the original.
Crazy Taxi 3: High Roller (2002)

Crazy Taxi 3.
The third game added nothing new to the gameplay, and as a result, the critical reception was harsh on the third installment. The game was release on the Xbox, then later in the arcades, and it features the first two levels, music tracks, and cab drivers from previous iterations with the additions of a new city, Glitter Oasis (Based on Las Vagas), four new cab drivers, and more music tracks.
The first two levels from the previous games have been re-design. The graphics have bump up to look better. The West Coast level from the original do feature all the familiar landmarks that players will remember, but they have been reconstructed - some of the buildings look a bit different from the original, and new areas have also been added, the new West Coast level is much bigger than the original. The Small Apple level from the second game have also been re-design so much that it doesn't resemble the original the Small Apple from Crazy Taxi 2; the re-design version also takes place during the night time as well.
The game was originally known as Crazy Taxi Next. It was also going to feature an online mode, multiplayer, and a day and night cycle along with the contain that was in the final version.
Crazy Taxi: Catch a Ride (2003)
A Game Boy Advance version of the original Crazy Taxi was made, it was develop by Graphics State and Publish by THQ (Sega had no involvement). The game's environment was render in 3-D, while the cab and pedestrians were render in sprites, due to the limitation on the Game Boy Advance's hardware.
Crazy Taxi (Redemption Game 2003)

The redemption game version of Crazy Taxi.
A Crazy Taxi redemption arcade game was made in 2003 by Sega's U.S division. The way the arcade cabinet is built, is it has a slop with a moving taxi cab in the middle, there are also eight targets at the far end which are the costumers. The rules of the game is the player drops a coin down the slop, and has the coin land on one of the eight targets to earn points.
Crazy Taxi: Fare Wars (2007)
A port of Crazy Taxi and Crazy Taxi 2 was created on the PSP. A multiplayer mode and the ability to customize the soundtrack was added. Several changes was made to both versions, all the in-game advertising was remove and so was the original soundtrack.
Other Media

The Crazy Taxi RC car.
Sega made a deal with DSIToys to make RC cars based on the cabs from the game in 2003. Sega saw this as a way to branch the Crazy Taxi series outside of video games.
Controversy
Electronic Arts and Fox Entertainment created their own version of Crazy Taxi in the form of Simpsons: Road Rage in 2001. The critical reception of that game was poor, critics label it as a "Crazy Taxi rip-off." Soon Sega file a law-sue on Electronic Arts and Fox Entertainment for patent infringement. The case between Sega, Fox Entertainment, and Electronic Arts was settled for a unknown amount of money.