Davy Wotton is an Arkansas guide who hails from the UK. His "Davy Knot" is an excellent near-100% knot that works best for small flies on light tippet.
(From: The Itinerant Angler)
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Animated Knots By Grog
16-20 knot
Clinch Knot Tippet to Fly
Borger Knot (Nailess nail knot)
I tested this knot for the past two years now, and it works.   I have never had it fail.  Read more here:
Castwell Knot