360 degree photos are growing in popularity. There are many variations, full panoramics, round panospheres etc. etc.  There are special cameras, software, tripods, lens and lot's of ways to spend money on it. If you are intriqued by the science behind it, there is a lot of math concepts you can study. If you just want some very quick abstracts and want to experiment, there is a filter called "Polar Coordinates" in Photoshop that can create nice effects within seconds. Below is a field in Alaska and a Vegas storm shot  I picked to give a fast example. Just go into the "Distort" menu under filters and click Polar Coordinates, and that is pretty much it. Usually you would use some cloning to clean up the lines where it joins. Even better if you take some 180 shots of cities, or landscapes. Below are some examples I did fast.
  
Check out this link on Flicr. http://fiveprime.org/hivemind/Tags/360,polar for more examples.