As a windsurfer, I am particularly interested in good spatial visualisations concerning wind including wind speeds and the wind direction. Wind barbs were invented to be the standard of visualising wind, but to my disappointment, leaflet offered no plugin to create wind barbs. I could have just loaded individual images as markers, but I wanted a flexible solution and so I created a Leaflet plugin which takes the Lat/Long of a point, along with wind speed and wind direction and generates the appropriate wind barb icon. For reasons of convenience I made only the centre circle clickable and I also included several options to style the wind barbs and last but not least, seeing that the plugin generates icons which are used in Leaflet markers, popups can easily be bound to the markers.
Example
The current progress and the plugin can be seen and downloaded on github.