Wife and I purchased an adjustable bed frame (highly recommend btw, highly) and the old frame was sitting there collecting dust so I turned it into a clamp rack as a Sunday project.
Looks like the pic is coming up sideways (again!). If I didn't have so much gosh darned trouble presenting pics, I'd probably upload some of my work but I'm so challenged to post a single pic that a whole spread of work seems like an exercise in frustration.
Regardless, very easy project that you could knock out in a little longer than it would take you to assemble the store-bought version (few hours, maybe 4) and save a couple hundred bucks.