Sigma offers its factory-refurbished Sigma 17-70mm f/2.8 DC Macro OS HSM Lens for Sigma, Canon, or Nikon (pictured) for $379 with free shipping. That's $120 under the lowest total price we could find for a new one. It features optical image stabilization. Update: The Canon and Nikon lenses are sold out.

Also available is the factory-refurbished Sigma 120-300mm f/2.8 DG OS HSM Lens for Canon for $2,699 with free shipping. That's $851 under the best price we could find for a new one. It features optical image stabilization. A 90-day Sigma warranty applies to both models.