Stealing the spotlight at Bonhams' 2010 Spring Fine Watches and Clocks Auction will be the 'Joker'. No, not Batman's arch enemy. Rather, a diamond watch winder made by Swisskubik and nicknamed the Joker. The compact cubic-shape masterpiece is encased in almost one kilogram of 18 carat white gold, while three of its sides are set with 3,876 round brilliant diamonds weighing more than 200 carats. Estimated between HK$2.8 million and HK$3.2 million, the Joker is probably the most luxurious watch winder ever made. Another star attraction will be a platinum watch with perpetual calendar and chronograph by Patek Philippe (ref. 3990). The original baguette diamond bezel features 2.77 carats of select diamonds. With fewer than a dozen of this model manufactured in the early 2000s, this watch is an extremely rare find (HK$2.2 million to HK$2.8 million). Other highlights include a Shanghai Watch rose-gold limited edition tourbillon wrist watch (HK$98,000 to HK$128,000); a Rolex Orchid Chameleon 18 carat gold ladies wrist watch from the 1960s (HK$24,000 to HK$42,000); an Urwerk PVD PT950 platinum limited edition wrist watch (HK$360,000 to HK$480,000); and a Cartier 18 carat gold skeletonised tourbillon wrist watch (HK$320,000 to HK$510,000).