Where did you get the idea for your most recent book?
I don't like this question because it's a little too specific and not useful for aspiring authors. It's also way too similar to, "How do you get inspiration?"
Anyway, here's a brief rundown on where the IDEAS came from for all my projects.
1.) The Silver Ninja Book One. This was inspired by Gray Fox, a character from Metal Gear Solid. However, the desire to write it came from a lack of strong female characters in mass media. Basically, I wanted a female commando who had a really cool cyber suit to give her superhuman abilities.
2.) The Silver Ninja Book Two, Indoctrination. This book was started by my desire to publish two books and to create an awesome female villain character. I had dreamt for the longest time of a hardened CIA Assassin going up against The Silver Ninja using a nanosuit of her own. Basically, I couldn't stop thinking about her and needed to write her story.
Any event that happens in the real world where I think to myself, "If only superheroes existed." That will probably serve as the kindle for a Silver Ninja story.
If I see something creepy or dream-like, that may inspire me for a horror story.
If I notice human behaviors and think of "What-if" scenarios, that may inspire me for a romance.
So like I said in one of my other answers. You need to experience life in order to get inspiration for your stories.