What have you done with UDAs?

[ponce via Digitalmars-d]

On Monday, 22 June 2015 at 19:09:40 UTC, weaselcat wrote:
> I never seem to use them for anything, has anyone else done 
> anything interesting with them?

I've used them along with reflection to describe OpenGL vertex 
formats from a struct.
https://github.com/d-gamedev-team/gfm/blob/master/opengl/gfm/opengl/vertex.d#L25

 From this thread it seems UDA are quite successful.