The Windlight viewer is back, and folks are having all kinds of fun playing with it's functionality. Torley's WindLight tips explain a ton of the options and effects that can be achieved with the viewer.
Known issues and bugs with Windlight are listed on the Jira.
Snapzilla is showing off WindLight pics like this by Tweed Silvera...
They're starting a new album of WindLight pics, the address for inclusion in the album is firstname.lastname@example.org
For a bunch of info on the First Look Windlight Viewer by Jeremy Linden, check the Knowledge Base Article of the Week on the official blog.