Cruis'n USA
Nitrous Boost
Get your name on the "Hot Lists", scroll to the bottom of the list, and hold left for about 35 seconds until the head comes rolling across the screen. Using any car in any race, you can now get a Nitrous Boost by press Brake, Brake, Brake, Gas, Brake, Gas. You can only use this once for every checkpoint passed.
Credit Goes To: Nintendo Power
 Nitrous Boost
 Secret Cars
 Secret Courses
 Flashing Lights Trick
Secret Cars
When on the Car Select screen, if you hold the C-Left, C-Down, and C-Up buttons, then move the Control Stick from car to car, you will notice that the ATV, School Bus, and the Police Car are available vehicles to race with.

Secret Courses
To race on the following courses, hold the specific buttons, then press Start to race:
Golden Gate Park - Hold the L Button, and also hold the C-Left and C-Down buttons. Golden Gate Park will replace US 101.

Indiana - Hold the L Button, and also hold the C-Up and C-Right buttons. Indiana will replace Beverly Hills.

San Francisco - Hold the L Button, and also hold the C-Right, and C-Down buttons. San Francisco will now replace the Grand Canyon.

Flashing Lights Trick
After you put your initials in on the "Hot Times" screen, you can press either up or down to scroll through the Hot Times. If you go all the way to the bottom to where the metal rollers are and hold the Left direction for about 35 seconds, a face of one of the designers will make an appearance and say "I love this job". After he says this, when you are racing any course with either the Police Car or the School Bus, if you press the Brake twice, then the Gas once, the lights will flash for as long as you hold the Gas. As soon as you let go, the lights go off. Do this as many times as you wish. Note: This code will only work if you are using the Police Car or the School Bus. It will not work with any other car.
Credit Goes To: N64cc