Prodigy
For the price of about $150, your family cat can be treated to the luxurious Window Cat Patio.

As pictured here, the self-contained unit mounts to a window using only a Phillips screwdriver.

Features of this unit include a lockable cat door to minimize heat loss; a ventilated housing structure; a translucent roof to monitor the pet's activity and sturdy vinyl and ABS plastic construction.

The only size restriction is that the window must be 22-1/2" to 36" wide.