Check out these velomobiles. Many aerodynamic features that have been discussed one way or another in this forum. There are three- and four-wheel models, from several manufacturers. Here are some videos:
Top 5 Velomobiles
Introducing the DFxl
(Gives a good inside and outside view, shows mechanics, etc.)
Capacity demonstration (funny).
QuattroVelo - Some views
Ride to the Rhine River on Quest Velomobile