GTA Liberty City Stories Glitches
It is possible to duplicate any amount of ammunition for a specific gun. This happens during any missions or odd jobs where you are driven by someone and have to shoot things with a crosshair and some type of automatic gun with unlimited ammo. Just have the gun in your inventory that you want to duplicate ammo selected before you start the mission or odd job. Certain missions where there is more than just the shooting part only require having the gun selected when you go into the shooting part of the mission. When the mission is completed or failed you should notice the selected gun has twice the initial ammo.
Infinite Time for Fires in Fire Truck Missions
To exploit this glitch it's just a matter of putting the fire out as the clock is going to hit 0. If done correctly, the timer will disappear allowing infinite time to cruise to the next fire.
Keep more than one vehicle in your garage.
Normaly you can only keep one vehicle in your garage due to the fact that if one vehicle is being stored the door will not open for the one your in, so get out of your car (a bike works easier) and push it next to the garage doors, when you get close enough it will open and let you push your vehicle into the garage. This is very handy when you want both a car and a bike at your fingertips.
Near Infinite Sprint Trick
Just tap default X button to sprint instead of holding it down. You cycle the sprint so it's like you never start. This can be done at any time; whether during a mission or exploration.