The windmill in Cley serves as a B&B, weddings and has a restaurant.
Built sometime in the 1810's. Wiki says this about it:

"The cap is now fixed and unable to turn to wind.
There are four double Patent sails with a span of 70 ft, carried on stocks 56 feet (17.07 m) long.
In 1819 the sails powered two pairs of French burr millstones, a flour mill and jumper
but by 1876 this had been increased to 3 pairs of stones and a smut machine had been added."