I have been building small portable solar systems for camping and power outages using 12 volts. You can run regular 110-volt devices by sending the 12 volts through an inverter, or more efficiently, there are some really great 12-volt products out there. Unfortunately, most of the 12-volt devices you can buy come with a cigarette lighter plug. These plugs are often of poor quality, and are much too bulky, especially when you want to hook up multiple things to a power source.
I went searching for a better connecting system, and it turns out the ham radio crowd found a great solution years ago. They are called Anderson Powerpoles, and are perhaps the perfect 12-volt connector. Some of the advantages:
* Flat wiping contact system (cleans the contacts every time you use them)
* Interchangeable genderless design
* Colored, modular housings
* Polarized, so you can’t hook things up wrong way
* 15/30/45 amp contacts use the same housing
I chopped off every cigarette lighter plug I have, and now put these on everything. Of course I still keep one lighter plug around (with a powerpole on the other end) for when I need juice from a car.