Fisheye lenses aren't for every occasion, but they are certainly a good idea in certain instances like this one where I wanted to get everything (house, deck and pool) in the photo. You can even see my shadow in the pool since I got up on top of the slide to take the picture (:g).
I like the way that the fisheye bends the trees in a whimsical fashion. Hey, if you are looking for an arbor of trees without any luck you can always take along a fisheye and create one!
Fisheyes are great for panorama photos. Here I wanted to get the old historical building, the beautiful palm trees and a hint of the modern building next door.
In this case I think that the fisheye effect gave the photo of this Mexican restaurant a more tropical feel as the deck and its tiki like umbrellas wrap around the building.
In this fisheye photo of my kitchen I added a white vignette to enhance the effect. My fisheye lens is an 8mm Rokinon (all manual...no auto settings). I keep the lens set at Infinity and f5.6. This is a Nikon mount lens. I used it for these photos on my Nikon D300 camera. The Rokinon lens is really built strong. It looks great, and the optics are terrific but it costs a pittance of what it's Nikon competitor sells for. Rokinon offers fisheye lenses for other camera bodies as well. I added one to my wishlist for my Olympus EM-5 too.
A fisheye is a great lens when you want to give your photography a creative charge. I like to put mine on the camera,then I leave all of my other lenses in the bag at home and just spend a few hours seeing what I can create with the fisheye. What do you think?