Computer Tower Grow Box

i wanna do something small just for myself, something i wouldn't have to share with my roommates. also i wanted it to be incognito have a single power port and look like something that would just be out in the open of my room. so i saw that their was a company already making this, but i can't see my self shelling out that cash for something i could make.

so enough of stoned ramblings, my question is this. what would make the best light for this project? i plan on growing the plants in hydro so root space wont be as much of problem.