Among the most most elegant articles of clothing for men is a well executed smoking jacket, which is why I am unable to resist re-posting the photo of Girolamo Stabile from Rubinacci Club's photos taken at a party they threw for the London launch of the self-published book about themselves (and if that is not self-referential what is?). Like most elegant things, the challenge with the smoking is finding an appropriate place to wear it, which is probably why Mr. Stabile wore his in what is usually considered an inappropriate venue (English custom reserves smoking jackets for wear at home or at one's club).
The two principal components of the best smoking jackets are silk velvet rather than the cotton stuff that is usually substituted, and the jacket frogs, so named because those things that replace the button on the front of his jacket look vaguely like the amphibians. London's Henry Poole had been the only firm I knew with a supply of silk velvet, which they stock principally for making ceremonial court dress, but apparently Rubinacci also has some since the photo caption, which admittedly I might have misinterpreted, appears to state that they made all the black tie garments pictured.
There were a number of years when I attended a rather dull New Year's celebration at my club simply for an excuse to wear the green velvet smoking jacket that may be the greatest extravagance in my closet in terms of cost per wearing. I would not wear mine at a book launch party, black tie or not, but I will admit that the thought is tempting. For, like Mr. Stabile's, it is an elegant thing.