Northern exposure had a couple of interesting trebuchet moments.
http://www.youtube.com/watch?v=MWxrt3bEnBs&feature=player_embedded
http://www.youtube.com/watch?v=rJgt-HO0_kY&feature=related
I wish I hadn't seen your dratted picture. I'm going to spend the next 2 hours stuck in a spread-sheet, and pulling prices. ;)
And figuring out how to explain to my heirs that daddy just has different hobbies....
I won't have to explain it to my grandsons... They get that kind of 'go boom' stuff.
/johnny