Softbox at work
My lampshade softbox at work with the use of a desklamp for the light source (not the one in the background of the shot).
It probably could have used another coat of paint. Or two.
Take an old lampshade and spray paint the outside with black paint. Protect the area around the lampshade with newspaper - use more than I did.
It might help to paint the inside of the lamp shade with white spray paint.
Used a plain white t-shirt, cut slightly larger than the lampshade and taped into place with duct tape. If you want to get fancy, you could use velcro on the lampshade and the t-shirt to adhere to each other.
You'll need to cut off the inner supports of the lampshade - a Dremel works great.
I used a desk lamp, which was not strong enough for the lamp shade, but a work light set up from Home Depot would be great. Clamp shade onto light source.