Luckily we don't have anywhere sensible to mount an anemometer (or at least that would give realistic readings if we did), so I'm able to resist my weather station lust for the most part.
On the other hand, I do have a bag of 1-wire temperature sensors on my desk, and may well get round to mounting one a decent distance from the house and away from direct sunlight[1] at some point. Having done that it would be silly not to make the most of it and add humidity and pressure sensors, and maybe even a rain gauge...
[1] I currently have an analogue thing sticking out on the end of a wire a few inches from an upstairs window sill, which reads a bit high in the cold, and very high if its sunny in the early afternoon. Makes some pretty graphs though.