What are the best road bike wheels?

Picking out "the best wheels" is as hopeless as selecting "the best car". First off, what's "best will be different for what type of riding you want to do. Secondly, once you get above a certain price range actual differences are so small that it's a matter of personal preference which is "best". Third, it's a question about parts + build. The best parts, but in a shoddy assembly will be much poorer than average parts in a good assembly.

Zipp and Rolf are often held to build good wheels, but a wheel from the top of the line from any manufacturer will be a nice part.