Red laser pointers are inexpensive and as available in drugstores and supermarkets today as they once were in electronic stores. You can increase the intensity of the laser beam in any inexpensive red laser pointer by removing the limiter circuit that was installed at the factory--although the strength of the laser will still be far below that of a professional and more expensive model since the limiter screw inside of the red laser pointer is left untouched. You will need a few hardware tools, but no electrical skills. Adult supervision is required if you are underage since a power tool and soldering iron will be used.
Put a sheet of newspaper on a table. Remove the battery cap from the back end of the red laser pointer. Remove the batteries from the battery compartment at the back end of the red laser pointer. Put the batteries and the battery cap aside for later.
Place the red laser pointer on the newspaper with the front end facing to the right. Rotate the red laser pointer so that the power button is facing up.
Place your left hand on the back end of the red laser pointer. Hold the red laser pointer down on the newspaper.
Pick up the power drill in your right hand. Place the drill bit against the top of the red laser pointer, just ahead of the power button.
Drill into the top of the red laser pointer. Stop drilling when the drill bit clears the top of the red laser pointer's shell. Put the portable drill aside.
Heat up the soldering iron for five minutes. Touch the tip of the soldering iron on the green square circuit board that can be seen through the hole in the top of the red laser pointer's shell.
Remove the tip of the soldering iron after 10 seconds have passed. Let the red laser pointer cool for five minutes. Unplug the soldering iron.
Put a piece of duct tape over the hole in the top of the red laser pointer's shell.
Put the batteries back into the battery compartment. Put the battery cap back onto the back end of the red laser pointer.
Aim the red laser pointer at a far wall. Depress the power switch to send a more powerful beam of laser light at the far wall.
Use the thinnest tip on the soldering iron as possible to prevent heating any other area of the laser pointer other than the limiter circuit.
Never aim the beam from a laser pointer at a person or domestic animal's eyes--the retina is extremely sensitive to the light of the laser and can be damaged from it.