The Original Pest Offense electronic mouse repellent is the best.

So if you're wondering what the best electronic mouse repellent is, I would personally have to recommend the Original Pest Offense. This device makes use of your electrical wiring and electromagnetic field to effectively drive out mice. It is actually very handy and simple to use. Plug it into a 120 volt wall outlet and allow it do its thing. It also has a built in surge protector and indicator light that also functions as a night light. A single Original Pest Offense will take care of an entire floor of a home.