Some say you can tell a person’s character by the way they shake your hand. Well, something similar may also be the case with buildings: Show me a store or home with an unusual doorknob, and the odds are that what’s inside will be interesting.

Given the city’s fascination with fashion, it is surprising how little attention has been given by designers and architects to the lowly doorknob. The vast majority of fashion boutiques feature doorknobs that are simple globes, bars, or thumb latches. In an era of revolving and automatic doors, perhaps such manual devices are relics of a non-lazy populace.

Distinctive door openers can grab the imagination. Take fashion designer Cesare Paciotti’s silver-colored dagger, at 833 Madison Ave. It looks sharp and intimidating but it doesn’t really cut, and the cognoscenti know it is Mr. Paciotti’s insignia, which can also be found on the bottom of his slick women’s shoes. The dagger is repeated on both sides of the boutique’s glass door.

An even more dramatic design can be found at Roberto Cavalli’s boutique, on the northeast corner of Madison Avenue at 63rd Street, where a realistic bronze snake appears to have wormed its way through and about the glass door in one continuous sculptural maneuver. This is the best in the city, or at least on this stretch of Madison Avenue.

Dolce & Gabbana has a large, chrome “D” and “G” on its double glass entrance doors at its chic boutique at 823 Madison Ave., while jewelry designer Chopard has an elaborate, elegantly scripted “C” on both sides of its entrance at 709 Madison Ave., reminiscent of some Persian calligraphic scrawl of incalculable beauty.

Clothing store Krizia has two pewter-colored abstract “Ks” on its glass doors, while Robert Vivier has a very large chrome rectangle, and Pouiellato has a discreet bronze ring at its side entrance at 741 Madison Ave.

Many of the most famous designer names have gone with the standard thumb-latch doorknobs on their buildings, although a few have opted for simple, tall, vertical pulls that are handsome but look like they should be operated only by strong-arm guards.

The most unusual can be found at the entrance door at Allegra Hicks’s boutique at 1007 Madison Ave. It appears to be a very large, hammered, gray-metal, sagging blob, but a lovely saleswoman inside explained that it is the designer’s “teardrop” logo, as she pointed to various other smaller such shapes on crockery and clothing in the boutique.

Surprisingly, the store with the world’s greatest, or at least most graceful, logo, Nike, has nothing special on its front doors on 57th Street between Fifth and Madison avenues.

You would think someone would simply sculpt a human hand as a welcoming and thankful handle.

Mr. Horsley is the editor of CityRealty.com.