Stumbled across some more normally-off synchronous rectifier parts in October, but was distracted.
These were released in the summer of 2008, by Linear Tech. Either they're low visibility on the net, or I've been using the wrong search terms.
pdf is updated to cover LTC4354, LTC4355, LTC4357 and LTC4358.
formatting link
LTC4356 has nothing to do with them, but I'd already found IT.....
RL