I have thought of installing a Battery Brain, see
www.batterybrain.com. It monitors your battery. When it detects power falling below the level required to start
your engine, it automatically isolates the battery from the electrical system.
There is a model with a wireless remote control. You could disconnect the power with this remote when you store the car for a longer period, but also when you park it somewhere. Instead of mounting the system on top of the battery as shown on the pictures, you could hide the box in a less visible place.
Of course there are better anti-theft systems, but the feature to disconnect the power appeals to me. Has anybody experience with the Battery Brain?
Martijn