I just found a fantastic Tumblr ( Make Your Own Path) for vintage off roading, sand dune buggies, jeeps, and homemade jalopies for sand dunes from Oregon to Michigan

I guess these are most accurately called Gow Jobs, or Jalopies... is there a better term for them?

Above, a Mickey Thompson truck I've never seen before, and
Below, Steve McQueen

For a lot more: http://bugsnbuggies.tumblr.com/