Have you ever noticed how sometimes even if there are slots available in a bike parking rack, some people will instead choose to lock their bike to a parking meter or sign post? This is because those racks aren't really conducive to securing the frame and both wheels, using a single U-lock. Montreal inventor Peter Krantz, however, has designed a rack that is.
Krantz's creation is known as the Next Gen Bike Rack, and here's an attempt at explaining how it works ...
When the rider approaches a parking space in the rack, they pull down an overhead spring-mounted steel box known as a docking station, to the height of their saddle (see the photo above). They then push their bike forward, so that the saddle enters that open-ended box, and so that their front wheel goes between a set of steel panels.
Next, they pull down a steel arm that's attached to a hinged door on the back of the docking station, closing that door across the back of the saddle in the process. They then run the base of their U-lock through a couple of loops on that arm, and run the lock's shackle through their rear wheel.
Got all that? In any case, the upshot is reportedly that the rear wheel is locked to the arm, the saddle is locked inside its steel box, and the bike as a whole can't be maneuvered enough to take off the wheel and saddle in order to steal the frame. While the front wheel isn't actually locked to anything, the idea is that thieves won't be able to get at its quick release lever or locking nuts.
Krantz additionally points out that the rack will protect the saddle from rain, it won't scratch the bike's paint, and it should accept a wide variety of frame sizes and styles. Also, of course, users don't have to remove their front wheel or seatpost.
Peter is now in the process of raising production funds for the Next Gen. There's currently no word on how the price of a commercialized version might compare to that of a conventional multi-bike rack.
Source: Next Gen Bike Racks via Dragon's Den
Much simpler solution: Get anti-theft locking skewers for the wheels, and you only need a solid D/U lock to lock the bike frame to any post/rack.
www.bikeforums.net/showthread.php/607513
As for defeating it, it looks ridiculously easy. Cut the loops with bolt cutters if you want to be stealthy or an angle cutter if you don't care about making noise, and in just a few seconds, everything is unlocked except for the rear wheel. Then just carry the whole bike away or replace the rear wheel and ride it away.
Bike lockers already exist and this probably costs about the same as those, given the complexity. Lockers provide weather protection and much higher security, protecting all small parts that could be removed with simple Allen wrenches.
Lockers addressing those concerns already exist. Some have a trapezoidal footprint rather than rectangular, so the narrow end where only the rear of a bike could fit would be far too uncomfortable for any human being. Other designs are constructed with see-through mesh with spaces too small to admit boltcutter jaws, so you couldn't conceal bombs in them.