Tool box option...need options

So im looking into getting a tool box for my new tacoma. i like the kow profile boxes but i was considering making one with my dad. He knows how to weld and made a pretty nice tool box for his tundra out of 1/8" steel. His is HEAVY and i dont need something thats going to weigh down the truck. Any other ideas on what material i can use besides aluminum? a thinner metal? if possible, im thinking of making or modifying one i buy,one that can use the rail system so i can slide it forward and back if need be

 

Don't make it out of steel....constant rust problem.
There are lots of choices but the best, IMO is the ProTech.

Once you see a ProTech up close, the rest look Walmart.
You have to pay to play, though.

 

your not going to get much lighter than aluminum unless you go plastic,and even than its close. as for thinner some of the tool boxes out of aluminum at some parts places are made of 1/16th. but are very flimsy. good luck