A DIY web portal

The objective is to develop a do-it-yourself public web portal that will contain a bunch of simple calculators (e.g., a CPC calculator where the user inputs the advertising cost (A), no of clicks (B), and the output is cost per click (A/B)) A few points to note: 1. This will be a public open-to-all portal so no login authentication is required at this point. 2. Suggested stack: Postgres, Python-Django, HTML5-AngularJS-Bootstrap-Javascript. 3. No server trip is required for the calculators to work. So its going to be all client side calculations. 4. Pls start your proposal with the word 'bingo!' to let me know you have read this :) 5. Usability and UX are the key. 6. The basic theme of the portal is: A DIY analysis platform. Target end users will be say marketing managers and pricing managers of various companies. 7. The list of calculators (divided into categories) is present at: [login to view URL] This is going to be a long-term engagement. In the subsequent phases, we will be adding in external data feeds at the back of this portal (data from Twitter/FB/Pinterest, macroeconomic data etc.) and building visualisations and charts using either Highcharts or D3 or both.