Just saw this link on SAR: OWL: World's first Drop-in Filter Adapter As someone who has a lens collection from DSLR it is quite tempting. I imagine next step of installing contacts to control aperture and have EXIF data available, as DEO has made this available for Canon and Contax to E-mount lens adapters already. Also great with manual focus ultra-wides like Rokinon or mirror lenses as efficient filter solution. My only gripe is the offerings are Nikon and Canon mount currently. Maybe with enough interest they would offer more options. Who is in?