4. Opus 6
Estimated Price: $320,000-$500,000
Price wise it comes appears subsequent to the Frank Muller Aetertnitas Mega 4 or the Patel Philippe Sky Moon Tourbillon. However, judging by the features, Harry Winston Opus 6 deserves to be ranked at par with both the beauties described above. Featuring a Double Tourbillon 30° and considered to be the brain-child of Greubel Forsey, the piece was manufactured in 2006. In what can be described as a brilliant specimen of horological complication, the Double Tourbillon 30° packs onto itself a one minute tourbillon and a four-minute tourbillon.