Immediately after I reported about Metabones' amazing “Speed Booster” adapter for EF lenses, a trusted source contacted me and told me that Metabones is working on a Speed Booster adapter for Canon FD lenses as well. This adapter should have a lower price tag, since it is missing the electronic part.
Unfortunately there was no exact information about the road map, i.e. when the adapter will be announced, just that it shouldn't take much time.
Cool news! Being able to use good old Canon FD lenses is of great interest for a lot of mirrorless camera users (Sony NEX' for first, but don't forget the rest of the MFT crowd).