Today on the chopping block we have the creations of Dan Feldman! Including the Danlock B and both the TRIP padlock and the MULTIP padlock.
MULTIP, TRIP, Danlock B
The Danlock B, I'm sure needs no introduction. It is sporadically available from Dan, directly through his website here. When I purchased it over a year ago, it was $120 USD, shipped to anywhere in the world. I can't speak for the price or availability now. Either way, back to the puzzle!