Steampunk is a sub-genre of science fiction and speculative fiction, frequently featuring elements of fantasy, that came into prominence in the 1980s and early 1990s. The term denotes works set in an era or world where steam power is still widely used — usually the 19th century, and often Victorian era England — but with prominent elements of either science fiction or fantasy, such as fictional technological inventions like those found in the works of H. G. Wells and Jules Verne, or real technological developments like the computer occurring at an earlier date. Other examples of steampunk contain alternate history-style presentations of "the path not taken" of such technology as dirigibles, analog computers, or digital mechanical computers (such as Charles Babbage's Analytical engine); these frequently are presented in an idealized light, or with a presumption of functionality. (Courtesy of wikipedia)
I've always enjoyed sci fi, Ray Bradbury, Doctor Who, Blade Runner, Isaac Asimov, J.R.R. Tolkien (although I found it difficult to get throught The Hobbit, I wasn't ready to learn a new language and alphabet). You would never know it to look at my closet, and except for a brief period in design school, it has never influenced my clothing decisions. But a lot of what I have seen of steampunk (when executed in a more sophisticated way) intrigues me. It reminds me of the clockworks in my grandmother's gold watch, and am on the lookout for steampunk details that can be incorporated in clothing without screaming "Look I'm wearing Steampunk".

The driving gloves, the collar, the pin, narrow lapel, you can bet what we are looking at is the ne plus ultra of fabrics and tailoring outside of the typical steampunk budget:). I'm only sorry that they didn't have a photograph of his reticulated rings.
Here are some details which may may be introduced without looking like a costume.
Buttons.

(courtesy of ebay seller treasurecastinc) I've never ordered from this vendor but they seem to have a pretty good rating.
Anthropologie has these cute laceup booties with metal buttons.

Azzedine Alaia - corset belt (ok probably not within our budgets but other versions are)