Frankly, the list of other genres of podcasts goes on and on. If you're feeling particularly inspired (and lucky), you might even successfully create a new genre with your podcast.
We could go on for quite some time with the many different types of podcasts available. But we won't. There are so many different, unique and talented people podcasting that new subjects are popping up daily. If you did not see a podcast that is similar to the one you do, then consider yourself lucky because you likely have a good niche for yourself. And just because you do see one that is similar to what you want to do, it does not mean you have to change. After all, Bewitched inspired I Dream of Jeannie, and The Addams Family inspired The Munsters. Think about what a loss it would be not to have I Dream of Jeannie and The Munsters.