Auctions specialize in anything collectible, from animation cels to fine wines to Chinese ceramics to Academy Awards fashions. The two major auction houses are Christie's, at 20 Rockefeller Plaza, 49th Street between Fifth and Sixth avenues (tel. 212/636-2000; www.christies.com), and 219 E. 67th St., between Second and Third avenues (tel. 212/606-0400); and Sotheby's, 1334 York Ave., at 72nd Street (tel. 212/606-7000; www.sothebys.com). Every now and then a celebrity estate goes up for auction (like Jackie O's and the duke and duchess of Windsor's so famously did). No matter what the auction, viewings are free and open to the public; full calendars are available online. If you plan to participate, be sure to review the catalog for price estimates beforehand and attend the sale preview for an advance look at the merchandise.

New York has other auction houses that are less well known (and less fraught with controversy) that you might want to consider, including Guernsey's, 108 1/2 East 73rd St., between Park and Lexington aves. (tel. 212/794-2280; www.guernseys.com), which focuses on modern collections and memorabilia (they auctioned off Muhammad Ali's training camp in 2003); and Tepper Galleries, 110 East 25th St., between Park and Lexington aves. (tel. 212/677-5300; www.teppergalleries.com), the city's oldest privately owned auction house, specializing in fine and decorative arts shows and estate sales.