The phone lenses made by Photojojo are awesome! They come in three styles fisheye, telephoto and wide angle. The lenses come with a magnetic ring that you stick around your cell phone camera lens. It has adhesive on one side and is magnetic. After that sets you simply let your lens attach magnetically to your camera and voila you are shooting with a camera lens on your cell phone!!
The lenses are around $20 for the wide angle and telephoto and $25 for the fisheye lens. Or you can buy all three for $50.
Take a look at my review here or you can go to their website for more. That site is www.photojojo.com