So you need an ultra-telephoto zoom lens for your DSLR? The Sigma 200-500mm Ultra-Telephoto Zoom Lens could be just what you need. Sure, it is more expensive than some cars, but this lens offers fast aperture of F2.8 at the 500mm and F5.6 at the 1000mm focal length. You also get a 72mm filter holder at the rear. Keep in mind that you need a Canon DSLR to take advantage of this.
This ultra telephoto zoom lens is useful for astrophotography, portraits, wildlife, and sports photography. A Nikon version of this is also available.