A heavy-duty flashlight as carried by Security, Police and Military forces around the world. For that matter, you may even have one like it around the house somewhere.
Bulb is modeled for your convenience, but not the filament. Add a spot to simulate the beam coming from it, or just put it in the character's hand so she can beat down the zombie trying to eat her face.
Batteries not included.
It's a little poly-heavy for older game engines, but it should be okay for more modern engines.