This is one opus I completed over the summer of 2004. A pretty tricky test of folding skill and diagram interpretation skill with (probably) over 400 folds, here's the Black Forest Cuckoo Clock. Yes, it's made from one piece of paper, a very long piece of paper. (IIRC, I used a piece of wrapping paper about 1x10ft)
I finally got it framed in July 2005: