[natermer]

Check out endless-sphere.com. There are people there doin home-built motors and designing controllers. 99% of the content is just people messing around with their bicycles or arguing over silly things, but there are a few very highly technical people.

Also there is a open source motor controller called VESC from Vedder Electronics.

http://vedder.se/2015/01/vesc-open-source-esc/

It's a modern controller with FOC modes and such things.

Originally designed for electric skateboards it has gone through many revisions and is a viable commercial product. The developer has a official vendor for buying the design, but there are many clones and variations of different prices and quality.

There are people on endless-sphere working on variations to scale it up for larger EVs.