Ed, here's a little trebuchet some (very skilled) guys knocked together on the shores of Loch Ness.
Mind you you would need a really Big Bolt to transport that one! wink

I'm not entirely sure if it's been fired in anger.
I think they're afraid they might hit Nessie!

1950 Chevy Advance Design 3100 in Scotland
In the Stovebolt Gallery
More pix on Flickr.
I've definately got this truck thing in my blood ... my DNA sequence has torque settings
"Of all the small nations of this earth,perhaps only the ancient Greeks surpass the Scots in their contribution to mankind" Winston Churchill.