Here's a great looking bronze countertop.
Zinc is also an option, and has that whole Parisian Bistro look.
My favorite, however, is copper.
Doesn't the copper on the dark wood just look incredible?
Copper is supposed to have antibacterial properties -- this article at HGTV says "A recent British study highlighted copper's antibacterial skills: E coli survived on stainless steel for 34 days, while on copper it lasted for only four hours," so you could justify something that looks this good in terms of health.
I don't know specific prices, but I believe these are in the same ballpark as granite countertops.
Metal countertops are another example of great kitchen designs from bars. You don't find many examples of metal countertops using a Google search, but try out "bar top" instead of countertop and you find many examples.
This seems like the sort of project that would be possible if you were very handy, and after finding an article on how to build a copper countertops on Whimsie, I see that it is possible, but probably difficult.
(Sorry for the long hiatus from blogging -- I find that I can only manage one outside project at a time, and I've spent a lot of time planning a real life renovation + addition to our house. As Ben pointed out, though, that really *should* be compatible with The Steampunk Home.)