Last year was my first year as a NaNoWriMo participant. If you asked me this time last month, I would have sadly shaken my head and admitted that I wouldn't participate this year. I had absolutely no ideas.
Then, just over a week ago, I got a flash of an idea (it was actually a combination of several aspects of other ideas I've had in the past). I started to write immediately and then decided to take a break and wait until November. That actually helped give me some time to pan out more of the idea.
I know NaNoWriMo can be time-cosuming and frustrating at times, but I'm looking forward to it.