Rear-wheel steering recumbent

Front-wheel drive, rear-wheel steering. I'm surprised this isn't more popular; seems much more elegant than routing the chain to the rear wheel.

[EDIT - apparently that's because it's impossible:]

"Moreover, a bicycle is principally a vehicle that is permanently losing its balance. So it must be corrected continuously by steering.
When losing your balance on a frontwheel-steered bicycle, you can turn the handlebars in a way that the front wheel moves directly under the centre of gravity of the bike.
On a RWSB, it's just going the wrong way: As you want to pull the rear wheel under the centre of gravity, the bike turns the other way, thus increasing the dis-balance." - source

Custom rear-wheel-steering recumbent
Post on the merits of rear-wheel-steering

Some really wild other rear-wheel steering concepts

Also, the mini-bike Kyle posted seems to use rear-wheel steering as well.