Ideas are cheap. Just Google for them. There are several guys here on HN who post regular "idea dumps" of their recent ideas they don't have time to implement.
If you want to do it that bad you'll think of something.
I recently handed in my resignation. I finish in 2 weeks. I don't have any new work to go to (yet), and my savings+overdraft will only get me through 1-2 months at most. The idea is that I'll do contract work to build up some reputation, then hopefully land some bigger projects and build a team. Perhaps give me the flexibility to work on personal projects that might go somewhere. I was like you, I kept saying I'd start a company when I had a good idea. In the end I realised it wasn't the lack of idea holding me back, it was the fear of failing. I decided that failing wasn't something to be afraid of and if I didn't try I'd eventually regret it.
[Obviously I can't say if it's gone well or not yet, but I've made it past the paralysis. Ask me again in 6 months if it was a good idea]
