Metabones Speed Boosters are having quite a success. But for the first time we will also have a second company offering a similar, cheaper (and likely inferior optical quality) product. The first and long-awaited Lens Turbo for Micro Four Thirds will be announced next week! It will be a Nikon Ai to MFT adapter. Unlike previous info we got that adapter will still have the first generation lens design as the NEX Lens Turbo (here on eBay). But it will have improved coating to reduce the “blue spot” issue.
A Lens Turbo for Canon EOS EF and Canon FD lenses will come as next in early 2014.
Example of how it works: If you buy the Nikon Ai 55mm f/1.2 for $250 on eBay (Click here), stick it on the Lens Turbo and you get a f/0.85 aperture and f/1.2 alike depth of field.
P.S.: All Nikon Ai lens auctions on eBay (Click here).