We had a local bicycle swap meet today and as far as retro mountain bike stuff goes there wasn't a whole lot but i found one of these things: a 1999 specialized disc brake adapter. I don't have a 1999 specialized anything, but i've got a couple old alloy Schwinns and i wondered if anyone had ever fitted a shark fin to something other than the specialized bikes they were intended for. My shcwinns both have forks with a disk provision and the dropouts are drilled for... something, so i figured it was a matter of putting the thing on there and getting a caliper and rotor that would work together.