Novoflex's Chestpod is a great way to lend support when shooting with long lenses in scenarios where monopods and tripods would be impractical or prohibited. It begins as a comfortable neckstrap, which articulates to a wide rubberized base that rests on your chest, usually just below your sternum. Attached to this base is an arm that ends with a swiveling plate which has a 1/4"-20 screw for attaching the tripod collar of the lens. Of course, with medium "fast" telephoto lenses such as an 85mm f/1.2 or f/1.4, 135mm f/2.0 or the like, you would attach the front of the Chestpod to the bottom of the camera.
In this way, the shooter achieves a stable triangle of vibration-reducing assistance for those longer teles. Great for capturing sharp shots of scenes (such as popular tourist destinations) whose controllers have implemented anti-tripod rules in an attempt to sell their pictures.
The Chestpod can be used upon its own, or in conjunction with a quick release adapter to speed up the attachment and detachment of the Chestpod and whatever you're attaching to it.