At SIHH 2011 there were quite a few ultra-thin watches introduced, only one skeletonized ultra-thin, though, the Richard Mille Extra Flat Automatic RM 033. Available in titanium (shown above), 18K white gold or red gold, each case is 45.70 mm in diameter and only 6.3 mm thick.
Powering the RM 033 Extra Flat Automatic is the Caliber RMXP1, a high tech skeleton automatic movement, measuring only 2.6 mm thick. A solid platinum monoblock micro-rotor winds the automatic movement and is visible through the exhibition sapphire caseback. The power reserve is 42 hours. The RM 033 has the same high-tech skeletonized design that is signature of all Richard Mille timepieces, but in a thinner form factor, and now in a round case. The thin design is quite good looking on the wrist, while still maintaining the same modern aesthetic that has made the Richard Mille brand so successful.
Retail is $70,000 in titanium, $85,000 in red gold, and $90,000 in white gold.