I ran across these and thought that I'd give them a try. They are made for trolling motors and can accept 10 and 8 gauge wire (and 6 gauge with an adapter). I'm going mount one in the front and rear bumpers so that I can hook up my air pump (and possibly other high current things) without having to pop the hood. I'm thinking of switching them with a relay but that will probably be further down the road.
FYI Marinco also makes some of the best 12-volt outlets going.
ConnectPro™ Receptacle & Plug