K-town... The small cabinet has a 70 watt HPS I bought and modifies from a security light at Home Depot and a project box housing from an old cpu to house the ballast. I have diagrams somewhere.
The other lights in there are CFLs.
The big box is scrap from a home remodel(free), homemade doors, A 400watt HPS ecolux (or something kit@ $115.00us), the fans are rated for 120 cfms run a static flow and were $20us each(Lowes) and a homemade cfl rail w/ 3 100+ watt cfls for blue spectrum to help balance out the red of the HPS.
I have a small "puter" fan for pushing air around inside the box. A passive intake w/ light trap from the left-side bottom.
I can fit 4 well pruned (here is where differnces arise) individuals growing inside. A sativa/indica mix is recommended unless you possess LST or bonsai skills. Otherwise a killer SOG method with as many ladies you can cram into that clown-car alos works.
There is room for tinkering and room for hydro. I vent straight out through the top and into my air returns wich have a double ionizer buffer before it reaches the air handler.
I use dirt for this rig, but be wary where your passive intake is w/ dirt cause them bugs find a way in. You can also seal this whole thing up tight but that is personal preference.
If you want to see more like this I beleive VideoMan built a nice one for shits-n-giggles.