The side-by-side bike:

 

The Twin Tri-rider (a tandem trike):

TwinTri-RiderRed

 

 

The elliptigo:

elliptigo

 

 

The Taga (combination bike/stroller):

Capture

 

 

The Yike Bike (Segway meets bike):

marina09

 

The Sideways Bike:

Snowboard Bike5

 

The Bullitt Cargo Bike:

bullitt

 

The Fliz Bike:

 

 ThisWay, a bike with a roof to protect you from the elements:

ThisWayRainLR_1

 

The Sada Bike, which folds into the size of an umbrella:

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