My ebay tool box. It's a simple aluminum box that I beefed up with 2 MasterLock hasps.
It provides secure storage for tools and recovery gear outside the cab. It doesn't block my bed rails so I can still run my canopy. And it sits low enough that I can still slide my sleeping deck over it for camping trips.
Basically, it does everything I need an empty friggin' box to do, and it didn't cost $500+. Yes, I'm looking at you, Weather Guard!