PHP + Yii Framework + jQuery + MySQL. It does everything you'll need - quickly and neatly. It's got the good bits of Ruby on Rails with the benefits of using

PHP + Yii Framework + jQuery + MySQL. It does everything you'll need - quickly and neatly. It's got the good bits of Ruby on Rails with the benefits of using PHP (huge amounts of tutorials, modules, components etc). Fuck worrying about what's cool, or what scales. You want to build a product that works so you can show it to people and see if they will pay money / use it.