Opteka 0.20X HD Super AF Wide Angle Fisheye Lens (Different Sizes) - Walmart.com
Engineers produce a fisheye lens that's completely flat | MIT News | Massachusetts Institute of Technology
Fisheye Or Wide-Angle Lens For Travel
What is a Wide Angle Lens? What Is a Fisheye Lens?
Amazon.com : Opteka 58MM 0.35x Fisheye Wide Angle Lens Compatible with Canon DSLR Cameras Including Macro Close Up Attachment : Camera Lenses : Electronics