Swiss luxury watchmaker Patek Philippe is marking the end of the 20th century with a unique giveaway and celebrating the new millennium with a monumental new timepiece, the Star Caliber 2000. The Geneva, Switzerland, firm announced in late 2000 that it would mark the end of the 20th century by giving owners of its timepieces the chance to win one of the last 10 complicated mechanical watches made by the company in that century. Customers were asked to send the reference and movement numbers of Patek Philippe watches purchased before Jan. 1, 2000, along with their name, address, and the name of their Patek Philippe dealer, to the Swiss watchmaker before Dec. 31. Watch owners also could register at the Patek Philippe Web site (www.patekphilippe.com) or by fax or mail. All 10 watches will be presented to the winners by Philippe Stern, chairman of the family-owned business, at a special re