I use Firefox 98% of the time.
I use Internet Explorer 1% of the time because there's a few websites that don't work in Firefox, but only with Internet Explorer.
I use Opera 1% of the time because there are some websites where transparent images are hidden on top of regular images preventing people from saving the regular image. One good example would be... Flickr. Opera allows me to prevent that image from loading and allows me to save the regular image.
