Tim - you joined the mirrorless revolution just in time! ; Have you seen this little beauty?: http://www.metabones.com/images/metabones/Speed%20Booster%20White%20Paper.pdf Looks like Canon EF and Nikon FX are coming first. ; I know you don't necessarily want to use the bigger lenses on the smaller body, but it is a fascinating technology and idea...a converter that allows you to attach full frame lenses to an APS-C body and achieve full-frame equivalent focal length and aperture. Stick a 50mm F2.8 lens on, and it will shoot as a 35mm F2 lens on the NEX, which with the crop factor of the camera applied, results in a 53.25mm F2.8 equivalent lens...effectively a match of full frame plus or minus some small change. I see this as most promising or interesting for low light work with primes...being able to shoot with a nice, fast prime and essentially wipe out the crop factor and maintain the same aperture equivalence sounds really nice! ; A 30mm F1.4 actually shoots as a 30mm F1.4. ; A 50mm F1.2 actually shoots as a 50mm F1.2 (or close enough to not matter much). ; Even the DOF matches full frame. Cool stuff! ; And for you M4:3 shooters, you'll have one made for your mount too! ; A full-frame 50mm lens on M4:3 using this adapter would be converted down to 35mm, then the 2x crop factor applied for a 70mm equivalent...certainly closer than the 100mm equivalent it would normally deliver...and the aperture would be closer effectively too.