Writing fiction – what topic or genre would you pick?

If you were to write a novel, what topic or genre would you pick? Or, put another, are there particular subjects or genres that appeal to you?

All the following genres would appeal to me if I was writing a novel:

- Sci-fi set in a future earth (Yes, I know, the sci-fi genre is such a clichéd stereotype about the type of fiction that developers read! )

- Horror

- Some aspect of technology e.g. a dsytopian future involving A.I.

There are types of fiction I enjoy reading but wouldn't attempt to write: thrillers, historical novels, fantasy.

If you were to write a novel, what subject would you pick? And for anyone who has written a novel (or is writing one currently) tell us about what you chose to write about.