What? It is, I took that pic with my nikkon d5100 can't you tell? Does it look like a five year old did it up in paint or something because you'd be wrong, I'm much older than that.
My PC grow box is 18"x18"x8", the CFL's at the top take up about 3" so it's more like 18"x15". 12/12 from seed and I still ran out of room too fast, I kept the lights almost touching the entire time too so it wouldn't stretch. Mostly just did it for the hell of it, I only built it to get the plants started until I moved them to a guerilla site.
Not sure about grow boxes specifically, but there have been a few successful experiments with bonsai gardening technique, funny, because we all know what japanese maple looks like. The party cup grow threads are pretty cool, too.