Secret Star/Global Pulse
In a Single Race or other normal racing mode, it will act as a Global Pulse. The spots for the Global Pulse will be different from the Practice ones. For instance - in Practice mode, the Star is under the red car that have a pole close to it as a ramp, while in Single Race, the Global Pulse appear to be on top of the very same car.
As a Practice Star
You must find a defined number of these on each track in Practice mode to unlock new cars. Only one star exist in each track at Practice mode and in Stunt Arena it has 20 Practice Stars (depends on Stunt Arena Track).
Once you find the star in all tracks of the determinated cup, such as the Bronze Cup ones (Toys in the Hood 1, Supermarket 2, Museum 1 and Botanical Garden), you'll be given new cars. Get all the stars in the Stunt Arena to unlock a new game mode - Clockwork Carnage, in which you will be still able to play the tracks as in the Single Race mode, but with 30 Clockworks at the same time!
As a Global Pulse
The best time to use the Global Pulse is when driving through an area that you have no problem navigating, otherwise you could end up spinning out and driving into walls for the duration of the Pulse's effects!
The Global Pulse is the only weapon that has its own dedicated pickup; this pickup is usually put in a hard-to-reach or out-of-the-way place, which requires either some skillful driving or a time sacrifice to get.
Sometimes, you may get this Global Pulse star when you pick up another normal pickup, but this is a rare chance.
In the track called Toytanic 1, you start with a Pulse Star, which was fixed in version 1.2.
As a Model
Its model can be found in the "/models/" directory as star.m
As a Tag
You must find this in battle tracks at random places. When taked, an electro-green pulse covers the car. The objective is to keep it with you for total battle time.