Country / State (Region) / City Data In JSON Format

I'm looking for Country / State (Region) / City data in JSON format. I thought I'd easily find a database (or even a web service) that lets me populate the drop down fields with accurate information. My preference of course is a downloadable database over the web service with limits.

I'm sure lot of dev folks here must have used it in their projects. I'd not mind paying for the database if it's offered at a reasonable price; but with a promise of latest and correct geo-data.