For my birthday this year Tammy surprised me with a new lens for my camera. She got me the Canon EF-S 10-22mm f/3.5-4.5 USM ultra-wide zoom lens. I've wanted an ultra-wide lens for a while because I find wide, landscape photography to be so much fun.
Here is an example shot with both lenses. Note the toaster is in the center of both shots. The one of the left is taken with my EF-S 17-85mm f/4-5.6 IS USM lens. (Click on the image to see a larger picture.)
You can see how much wider the shot is right away. There is some distortion on the corners of the shot which is unavoidable with such a wide lens.
I can't wait to give this a shot on some outdoor photography in the summer.