A nice option for the laserlyte trainer system - LaserLyte Compact Laser Pistol Trainer

I have the other model of this trainer where you insert the bore site and use that. The issue with the bore site I have is it eats batteries like a monster. You have to disassemble it after each session or the next time you try to use it the batteries will be dead. SO far this model with the built in laser the battery life is much better. I have only had the new model for a little over a week. But the batteries are still good. (why they can't put an on\off switch in these I don't understand)
Over all I recommend this tool in addition to your other training methods.