Great Chi Sao clips:
tan, huen sao:
http://www.youtube.com/watch?v=onA-Jv8Ft9E
chum kiu:
http://www.youtube.com/watch?v=PDpQrIuwxwo
bon sao discussion:
http://www.youtube.com/watch?v=OFuqC6CTKV8
lop-sao position and gaining the line:
http://www.youtube.com/watch?v=koR_4Eq0DcQ