Keep interviewing while building, you'll need to be making revenue to sell at a multiplier. So I'd think about building something you would enjoy running. Google and read about the slow SaaS ramp of death. It's probably not an immediate solution to not being able to find a job.

Check out Rob Walling and StartUpsForTheRestOfUs, great podcast and lots of great advice.

Check out his stair step approach. Basically start out with a simple product. An info product, plugin or package and then keep leveling up to get to a SaaS.

Good luck, keep those resumes going out.