One of my fellow club members (Coastal Cruisers) was in need of a roof rack, after looking for a while and finding the usual brands that did not do the trick he called me and see what I could do.
Now I've been planning on building these for a while now but never got around to it, so now I have an excuse.
The history, Unistrut ( http://www.unistrut.us/ ), used to make amazing roof racks for trucks, I actually have them on my truck and have been abusing them for the past 6 years with no issues. They stopped about 5 years ago and no longer produce them, they also never patented the idea either.
After my use of them I came up with a stronger design and even more options. The really cool thing about the Unistrut product (and other engineered strut of similar design) is you can build almost anything out of it, countless brackets, countless options, it's actually engineered and approved for structural use. (I'm attaching some pics below of the original Unistrut rack setup on my truck).
My design is a little different, and works with all engineered strut systems of similar design:
roof rack mount.JPG