Ah, at last my dream come true. Air free tires, well actually taking the air out and putting in foam instead. I saw those lawn tractor tires at Les Swab a while back and asked them if they knew the company that filled the tires with foam so I could get ahold of them. They were not going to give away business of course, so they avoided my question completely. haha
Now, here is a site that talks about foam filled tires. I have lived on a road that is filled with sharp rocks (it is really a goat trail) and I have flats every year. Some tires have just a hole big enough that the tire shop won't repair them, so I have to buy new ones. I kept the old flat tires for just the day I could get the foam and fill them up myself. A little glue in the hole will make sure nothing comes running out, but after that the foam hardens and no more worry.
So if you always wanted to have a worry free tire (unless it blows off the rim in some high speed accident even with foam in it) then this may be your solution.
Now if anyone wants to get into the business, they will help you on this page to do it at home.
Of course I am the type of person who thinks if there is a will, there is a way to do it and if they can do it, so can I. Well, by just getting ahold of some of the foam used in cans I think I can drum up a mold for the inner part of my tire and fill it myself without the machine. (They say it is not expensive).
It may have pictures of bicycles on the page, but in the reading it says you can do any size tire and will hold thousands of pounds per tire. Works for me.
Thought I would share.