I have of recent undertaken a lot of handbuilt Brompton wheel projects, Lightweight front wheelbuilds, Schmidt & Son Dynamo builds and standard and custom rim.
There is quite a bit being made availble now for the small wheel market and more and more in hub applications.
Phil Wood, Shimano, Bromptons own supa light and as mentioned Scmidt and Son
dynamo hubs.
Because I handbuild the wheels basically anything is possible I have built b speed sturmey rear wheels Rohlhoff and Shimano 8 speed alfine and as I have a great relationship with Paul Villiers from Villiers Velo rear trainale modifictaions to suit applications are not a problem.