The Metabones Micro Four Thirds to Canon EF Speedbooster adapter was part of recent news, so if you're looking at grabbing a Canon EF Lens here's the current list of price drops via B&H.
Canon EF 400mm f/2.8L IS II USM Lens : $1000 off : Final Price : $10,499.00
Canon EF 500mm f/4L IS II USM Lens : $1000 off : $9,499.00
Canon EF 600mm f/4L IS II USM Lens : $1000 off : $11,999.00
Canon EF 300mm f/2.8L IS II USM Lens : $700 off : $6,599.00
Canon EF 800mm f/5.6L IS USM Lens : $500 off : $13,499.00
Canon EF 14mm f/2.8L II USM Lens : $110 off : $2,249.00
Canon EF 24mm f/1.4L II USM Lens : $100 off : $1,649.00
Canon EF 85mm f/1.2L II USM Lens : $100 off : $2,099.00
Canon EF 100mm f/2.8L Macro IS USM Lens : $100 off : $949.00
Canon EF 180mm f/3.5L Macro USM Lens : $80 off : $1,499.00
Canon EF 50mm f/1.2L USM Lens : $70 off : $1,549.00
Canon EF 135mm f/2L USM Lens : $40 off : $1,049.00
Canon EF 200mm f/2.8L II USM Lens : $40 off : $779.99
Canon EF 24-70mm f/4L IS USM Lens : $500 off : Final Price: $999.00
Canon EF 24-70mm f/2.8L II USM Lens : $200 off : $2,099.00
Canon EF 70-200mm f/2.8L IS II USM Lens : $200 off : $2,299.00
Canon EF 8-15mm f/4L Fisheye USM Lens : $150 off : $1,349.00
Canon EF 70-300mm f/4-5.6L IS USM Lens : $150 off : $1,449.00
Canon EF 28-300mm f/3.5-5.6L IS USM Lens : $140 off : $2,549.00
Canon EF 70-200mm f/4L IS USM Lens : $50 off : $1,299.00
Canon EF-S 55-250mm f/4-5.6 IS II Lens : $50 off : $249.99
Canon EF-S 55-250mm f/4-5.6 IS STM Lens : $50 off : $299.00
Canon TS-E 17mm f/4L Tilt-Shift Lens : $250 off : Final Price: $2,249.00
Canon TS-E 24mm f/3.5L II Tilt-Shift Lens : $200 off : $1,999.00
