An interview with Professor Vijay Pande,
one of the chief scientists in the protein folding program. He explains with a video representation how often a protein folding, can be like a drunk reverse parking. They can get into a 'knot', and have to unfold the section 'tangled,' and try again. They continue to fold until a solid unit is formed, with active units free. The complexity of the folds, and the specific nature in which they can fold, make the packing and unpacking of a cell nucleus as a prime example, something that is as easy to imagine as a Billion years.
By the way the team in the video have made the top ten.
http://fah-web.stanford.edu/cgi-bin/main.py?qtype=teamstats